## 1. What are Perceptual Experiences?



This entry will focus exclusively on the contents of perceptual
*experiences*. It is definitional of experience, as the term is
used here, that they have some phenomenal character, or more briefly,
some phenomenology. The phenomenology of an experience is what it is
like for the subject to have it. At any given waking moment, one
normally has experiences in some (perhaps all) of the five sense
modalities, along with proprioceptive experience of some sort. Like
occurrent emotions and background moods, these contribute to
one's *overall experience*. Each of five sense modalities
seems to be accompanied by a distinctive kind of phenomenology.
Sometimes the boundaries between them can be hard to draw, for example
between olfactory and gustatory phenomenology, kinesthetic experience
and haptic-tactile experience (that is, tactile experiences involving
movement rather than just pressure sensation), and perhaps, in some
cases, between the latter two and visual experience (on the last point
see Press *et al*. 2004, Kennett *et al*. 2001,
Fotopoulou *et al*. 2009; on distinguishing the senses, see
Stokes, Matthen and Briggs 2014, Wilson and Macpherson 2018). Despite
these difficulties, some rough distinctions can be drawn: the
difference between seeing red and seeing blue is not a difference in
how things sound, or in how one's body feels.



In what follows, "experiences" will be restricted to
experiences in any of the five modalities or kinesthetic experience or
some combination. In the analytic tradition, most of the questions
discussed in this entry have been addressed with regard to visual
experience and pain. In contrast, the phenomenological tradition
explored similar questions with respect to other modalities. For
instance, Husserl's exploration of auditory experience of
hearing a melody is central to his discussion of the experience of
time (see the entries on
 phenomenology,
 auditory perception, and the
 perception of time).
 In principle, however, the questions addressed here could be raised
with respect to any kind of experience.


## 2. Contents as Accuracy Conditions



When one speaks of the contents of a bucket, one is talking about what
is spatially inside the bucket. An analogous use of "the
contents of perception" would pick out what is 'in the
mind' when one has a perceptual experience. In contrast, when
one speaks of the contents of a newspaper, one is talking about what
information the newspaper stories convey. Many contemporary uses of
"the contents of perception" take such contents to be
analogous to the contents of a newspaper story, rather than the
contents of a bucket. This notion of content can straightforwardly
accommodate the idea that there is such a thing as the
'testimony of the senses'.



One influential version of the idea that the contents of perception
are analogous to the contents of a newspaper story holds that the
contents of an experience are given by the conditions under which it
is accurate. What an experience conveys to the subject, according to
this conception, is that those conditions are satisfied.



On the conception of contents as given by accuracy conditions, there
is a broad analogy between the contents of experience and the contents
of thoughts and utterances, in that both contents are assessable for
accuracy. Suppose I utter the sentence "Dogs are lively, loyal
creatures" and thereby express my belief that dogs are lively,
loyal creatures. The content of my utterance is what I assert, and the
content of my belief is what I believe--in both cases, that dogs
are lively, loyal creatures. Usually these contents are thought of as
some kind of proposition--an abstract object that is the kind of
thing that can be true or false (see the entry on
 structured propositions).
 Notice that both the utterance and the belief are assessable for
truth: their content is true just in case dogs really are lively,
loyal creatures.



In the case of beliefs and utterances, it is not just their contents
that are assessable for accuracy (where accuracy is truth); the
beliefs and utterances themselves are as well. A belief or utterance
inherits its truth-value from the truth-value of its content. This
stands in contrast to desires or hopes, which may have contents that
are assessable for accuracy, but are not themselves so assessable. If
experiences have accuracy conditions, then they are like beliefs and
utterances in this respect, and unlike desires and hopes.



The conception of the contents of experience as given by its accuracy
condition can be motivated by the idea that one can be misled by
one's experiences. Suppose you see a fish while unwittingly
looking in a mirror. It may look as if there is a red fish in front of
you, when in fact the red fish you see is behind you and there is no
fish at all in front of you. Similarly, in auditory or olfactory
hallucinations, one may seem to hear voices when in fact no one is
speaking, or to smell an odor when in fact nothing is emitting that
smell. In phantom limb pain, one feels pain as located where
one's limb used to be but is no longer. These are cases of being
misled by one's senses, and it is natural to say that in these
cases things are not as they appear to be.



Once one recognizes the datum that one can be misled by one's
senses, it is a further claim that experiences themselves can be
assessed for accuracy. It is a further claim, because one might be
misled by something that is not itself assessable for accuracy: e.g.,
one might be misled by the car in the driveway into thinking that your
neighbor is home. So the fact that something plays the role of
misleading you does not show that it is assessable for accuracy. But
in the case of experiences, this further claim is motivated in the
following way. Given an experience--either one we actually have,
or a hypothetical one--we at least sometimes have intuitions
about whether the experience is accurate ("veridical") or
inaccurate ("falsidical"). To this extent, we seem to be
able to assess experiences for accuracy.



When we assess an experience as accurate or inaccurate, we consider
how things are in the world. This suggests that experiences which can
be assessed for accuracy are associated with accuracy
*conditions*: conditions under which the experience is
accurate. When we have intuitions about whether an experience is
accurate, we at least sometimes also have intuitions about the
conditions under which it would be accurate. (For discussion of such
intuitions, see Siewert (1998), chapter 7, Schellenberg (2018). Going
with this, we seem to have intuitions about when experiences are
incorrect.



In large part, our intuitions about when experiences are accurate
concern objects and properties. For instance, many have the intuition
that the following experience is falsidical: you see a fish that
appears blue to you, but is actually red. According to the intuition,
the fish's failing to be blue suffices for the experience to be
falsidical. Intuitively, for the experience to be accurate, the fish
in question must really be blue. It is an open question how specific
and how extensive such intuitions are, hence to what extent such
intuitions can reveal which accuracy conditions experiences have,
assuming that they have accuracy conditions at all. But so long as
there are some such intuitions, there is a prima facie case for
experiences having accuracy conditions.


### 2.1 Do Experiences Have Accuracy Conditions?



Some philosophers deny that experiences have accuracy conditions. Such
philosophers must offer a different account of what is happening in
cases where one is misled by one's senses, and they must dismiss
or explain away putative intuitions about the accuracy or inaccuracy
of experiences. A natural way to do so is to confine accuracy and
inaccuracy to the level of belief, further downstream from
experience.



There are a number of positions that deny that experiences have
accuracy conditions (Wilson and Locatelli 2017). All these positions
deny this claim on the grounds that it is not supported by either the
metaphysics of experience or by its phenomenology. The positions
differ, however, on their positive views of the metaphysics and
phenomenology of experience.



The first position is the view that experiences are raw feels, or
sensory affectations of the subject, that do not purport to represent
the world in any way at all. The eighteenth-century philosopher
 Thomas Reid
 held a view of this sort: Reid argued that experiences have a sensory
part that is a mere raw feel, and that is independent of judgments
about how things are in the environment. (He took the latter
essentially to involve concepts). One might, on this view, speak more
broadly about experiences as having two parts, sensory part and a
judgment part; or one might speak more narrowly about experience as
being limited to the sensory part that is typically accompanied by
judgment. Which way one speaks is merely a matter of terminology. The
core feature of the view is its cleavage between the sensory aspect of
experiences, on the one hand, and assessability for accuracy, on the
other. Given a judgement that occurs simultaneously with a sensation,
one could in principle make that very same judgment without having any
sensation, and one could in principle have those very sensations
without making any judgments. That is the force of saying that these
two aspects, sensation and judgment, are independent. If experiences
are understood narrowly as being limited to the sensory part, then
they are not assessable for accuracy; and if they are understood
broadly as having both a sensory part and a judgmental part, then it
is only the latter that is assessable for accuracy.



The second position is a version of *adverbialism* about visual
experiences, according to which such experiences are nothing more than
modifications of a subject that can be characterized by specialized
adverbs specifying how one is visually 'appeared-to'.
E.g., normally, when one sees a red tomato, one is appeared to red-ly
and round-ly. Visual experience, on this view, does not by itself even
purport to present one with objects or their properties. There are
thus no accuracy conditions associated with such experiences. Instead,
on this view, to be misled by one's sense is to end up with a
false belief that is caused by one's experience. (For further
discussion of adverbialism, see
 the problem of perception;
 also Chisholm 1957, Ducasse 1942, Tye 1984, Sellars 1975, and for
critical discussion, Jackson 1977). Strictly speaking, it should be
noted that so long as the core thesis of adverbialism is that
experiences are modifications or properties of the subject,
adverbialism leaves open whether experiences are assessable for
accuracy or not. For all that core thesis says, being appeared-to
*F*-ly could be a way of representing that something is
*F*. Historically, adverbialists' main motivation was to
oppose the act-object conception of experience, according to which
experiences are structured by an act of awareness, on the one hand,
and an object of awareness, on the other. Early formulations of the
view presented it as a view according which experiences were not
assessable for accuracy.



The third position is that at least some perceptual experiences come
in degrees that correspond to degrees of uncertainty. Compare: there
is straight answer to the question "Is the sound I hear a
coyote?", when you are uncertain whether the sound comes from a
coyote or a human baby. You cannot simply answer Yes or No to express
your opinion; you have to hedge. If you are in such a state of
uncertainty, it might seem, then there no way the world could be in
order for your state to be accurate or inaccurate. By analogy, on the
third position, experiences sometimes reflect uncertainty in a way
that leaves them with no accuracy conditions (Madary 2012, Morrison
2015, Munton 2016, Vance 2020, Raleigh and Vindrola 2020). There is a
fourth position that denies that experiences have accuracy conditions.
This position starts with the claim that some experiences consist in a
chunk of the environment--for instance, a lavender
bush--being perceptually presented to a subject, so that both the
lavender bush and the perceptual relation between it and the subject
are constituents of the experience. (Note that this is more specific
than the view that says merely that *perception* of public
objects is 'direct'. That view is silent on what the
nature of perceptual experience is). According to one version of this
view, when you see a lavender bush, some of its properties are
presented to you, and your experience consists in your being so
related to the bush and those of its properties that are presenting
themselves to you. You could have an experience that was
indistinguishable from one of so seeing that very lavender bush: as it
might be, an experience of seeing a different lavender bush, or a
hallucination that was indistinguishable from the original experience.
But neither of these experiences, according to this view, would be the
same sort of experience as the experience of seeing the original
lavender bush. Martin (2006) and Smith (2002) call this view
"naive realism". Another version of this approach,
developed by Johnston (2006) and (2014), develops the idea that
perceivers are presented with instances of properties rather than with
universals. Note that both Martin and Smith's versions are
simply silent on the nature of hallucinatory experiences. (For more on
naive realism see the entry on
 the disjunctive theory of perception).




As stated so far, naive realism is neutral on whether any
experiences have accuracy conditions. A version of the view, however,
explicitly denies this. This version holds that experiences are
analogous to chunks of the environment that clearly lack accuracy
conditions. The lawn chair on the deck is not the kind of thing that
can be accurate or inaccurate (though it may figure in the accuracy
conditions of an utterance, such as an utterance of "that is a
lawn chair"). Travis (2004, 2013) develops naive realism in
just this way. He also offers further reasons for denying that
experiences have accuracy conditions. Travis agrees that in having an
experience one may represent that such-and-such is the case. He holds,
however, that there is no unique 'taking' associated with
an experience, and experience is only ever an input to representation,
never the result of it. One of Travis's examples is this: if you
see Sid and Pia touch hands at the dinner table, you make take them to
be trysting. But considered independently of this
'taking', your experience simply consists in being
presented with an unrepeatable, particular chunk of the environment,
namely Sid and Pia at the table touching hands. (The notion of being
'presented with' is left as primitive). Accuracy
conditions come into the picture only after you take the environment
as it is presented to you to be some specific, potentially repeatable
way. So according to Travis, the experience does not map onto any
unique set of accuracy conditions. Since illusions involve inaccuracy,
by Travis's lights illusory experiences are experiences that
have been 'taken' in such a way that the
'taking' is false.



A fifth position that denies that experiences have accuracy conditions
says that experiences are raw feels, but also holds that all
experiences have the same structure as perception of objects. On this
view, experience consists in immediately perceiving private objects
known as *sense-data*. According to sense-datum theories, when
your experience is a case of perceiving a public object, such as a
white wall that looks red, you *indirectly* perceive the wall
by immediately perceiving a red sense-datum. In general, sense-data
really have the properties that public objects look to have. In this
way your having (i.e., immediately perceiving) the sense-data you do
is supposed to account for what it is for a public object to appear to
you to be a certain way; and you have sense-data whether or not there
is any public object that you indirectly perceive by immediately
perceiving them.



It should be noted that if the core commitment of sense-datum theories
is that one immediately perceives mental objects in experience, then
sense-datum theories are neutral on whether experiences are assessable
for accuracy. From the fact that one perceives (or immediately
perceives) a particular object (be it a public object or a private
mental one), nothing at all follows about whether the experience of so
perceiving is assessable for accuracy or not (for more on sense-datum
theories, see the entries on
 sense data
 and the
 problem of perception).
 Jackson (1977) defends a version of the sense-datum view according to
which experiences are *not* assessable for accuracy.



All of these positions except the third one could be seen as offering
construals of the contents of the perceiver's mind, where these
are analogous to the contents of a bucket. Such construals contrast
with the newspaper model of perceptual contents, and more specifically
with the conception of contents as the accuracy conditions of
experience. Henceforth 'the contents of experience' will
be restricted to a notion that says that the contents of an experience
are the conditions of accuracy associated with it. The claim that
experiences have contents in this sense is substantive, and, as we
have seen, is denied by some philosophers. But many philosophers
accept that experiences have contents in this sense, and this
conception of the contents of experience dominates the recent
philosophical literature on perception. Defenses of the thesis that
experiences have contents can be found in Byrne 2009, Pautz 2010,
Schellenberg 2018, and Siegel 2010a and 2010b, and criticisms of those
defenses in Breckenridge 2007 and Wilson and Locatelli (2017).


### 2.2 Beliefs and Experiences



There are many ways of developing the idea that experiences are
assessable for accuracy. One idea is that the contents of experience
derive in some fashion from the contents of beliefs, so that
experiences bear some constitutive link to beliefs. Three sorts of
constitutive links to belief have been discussed in the literature.
The first is that experiences are *acquisitions* of beliefs;
the second is that they are *dispositions* to form beliefs; the
third is that they are *grounds* of dispositions to form
beliefs. A fourth position simply identifies experiences with beliefs
about how things look (Gluer 2009), or even more simply, with beliefs
whose content characterizes the way things look (Bryne 2016).



First, suppose experiences are *acquisition of beliefs* formed
by a standard use of a perceptual apparatus. When applied to visual
experiences, this view says that for as long as you see something that
looks like a red, shiny fish in front of you, you are acquiring a
belief that there is a red, shiny fish in front of you. The content of
experience, on this view, will be the same as the content of the
beliefs with whose acquisition the experience is identical. And what
makes a content the content of an experience, as opposed to some other
kind of mental state, will be whatever makes it the content of those
beliefs. (This view is critically discussed by Pitcher in his 1971,
chapter 2.)



A standard objection to so identifying experiences with the
acquisition of beliefs is that one may not believe that things are the
way they appear. (This objection is discussed by Pitcher, op cit, and
by Armstrong 1968). For instance, if you have background knowledge
that despite appearances there is no red shiny fish in front of you,
then you will not believe that there is one. To accommodate this
objection, the relation between experiences and the acquisition of
beliefs must be something other than identity.



Second, suppose that experiences are *dispositions* on the part
of the subject of the experience to form beliefs. This view is
defended by D. Armstrong (1968), G. Pitcher (1971), D. Dennett (1991).
*Which* disposition an experience is, on this view, depends on
how things appear to the subject in the experience. For instance, if
you seem to see a red shiny fish in front of you, then (on this view)
you have a disposition to believe that there is a fish in front of
you, and your experience is identical with this disposition.



If experiences are dispositions on the part of the subject to form
beliefs about how things appear to her, a natural accompanying view
about the contents of experience is that these just are the contents
of the beliefs one is disposed to form. According to this view, what
makes some contents contents of *experience*, as opposed to
being contents of some other kind of mental state, is in part that one
is *disposed to believe* those contents.



One could then develop the idea that experiences are assessable for
accuracy in the following way:


1. Having an experience consists in being disposed to form certain
beliefs.
2. The conditions under which the experience is accurate (i.e., its
contents) are the same as the conditions under which the beliefs one
is constitutively disposed to form in having the experience are
accurate. (Equivalently, the contents of experience are the contents
of the beliefs one is constitutively disposed to form in having
it).



Pitcher's view in his 1971 is (a). Claim (b) is a natural
extension of (a), given the assumption that beliefs have accuracy
conditions. (Pitcher doesn't talk explicitly about accuracy
conditions).



One difficulty with (a), and so with (a) and (b), is that it leaves
open how the relevant dispositions must be grounded. You could be
disposed to believe that there was music playing next door because
someone told you it was, and yet, it seems, not hear or even seem to
hear any music: you might be totally deaf, for instance. In this case
you would not have any auditory experience of music, despite being
disposed to believe that music is playing. So proponents of (a) seem
well-advised to specify an appropriate ground for the dispositions
they identify with experiences, so that they do not misclassify as
experiences events that intuitively are not experiences.



This brings us to the third position on the relation between
experience and belief: that experiences are perceptual grounds of
dispositions to form beliefs. Just what a specifically perceptual
ground is has to be spelled out--a natural suggestion is that it
requires a certain etiology involving sensory organs, or functional
equivalents. Given this third position, a natural accompanying
conception of the contents of an experience is that they are the same
as the contents of beliefs that one is disposed to form in having the
experience (claim (b) above). However, another version of the view
might hold that although the experience itself is constitutively
linked to beliefs, it does not have *contents* that are
constitutively linked to the contents of the beliefs.



Claim (b) above, which identifies the contents of an experience with
contents of beliefs one is disposed to form in having the experience,
assumes that the contents of both kinds of state can be the same. Some
philosophers have argued that the contents of such states must differ.
If this is correct then none of the views here mentioned can be
correct as stated. (For discussion of how the views might be modified,
see
 Section 6.2
 below, and the entry on
 non-conceptual content.)
 



Another objection to views that posit constitutive links between
experiences and beliefs, or between experiential contents and belief
contents focuses on primitive creatures that can have experiences,
even though they lack the capacity and disposition to form beliefs.
Such creatures would seem to be impossible if experiences were
constitutively linked to beliefs, as the views discussed here hold.
This objection seems to apply to the position that identifies
experiences with beliefs about the ways things look (defended by
Gluer 2009). In contrast, Gluer's (2009) view seems
immune from the objection that assimilating perceptual experience to
belief would entail that subjects of known illusions have
contradictory beliefs, and so are irrational. This objection applies
to Byrne (2016), who argues that this consequence is plausible. 


### 2.3 Content and Attitude



Instead of holding that the perceptual content derives from the
content of belief, one might instead hold that the contents of
perception and the contents of belief are in some sense analogous, and
more generally that experiences and beliefs are similarly structured
by contents on the one hand, and a relation to those contents, on the
other.



Beliefs are often thought to be relations to contents, and contents of
beliefs are often thought to be contents that one can stand in other
relations toward, besides belief. Such relations are sometimes called
'attitudes', where examples of these are supposed to be
notions from folk-psychology such as hoping, wanting, or supposing.
However, it is useful to construe the notion of 'attitude'
more broadly, so that it is more generally a way of having content.
Subpersonal states of visual processing, if they are informational
states with accuracy conditions (and so with contents in our sense),
will instantiate ways of having content; so would the propositional
attitudes as they are traditionally conceived. From now on
'attitudes' will be relations in which one can stand to
contents, when one has a contentful mental state. Both philosophers
and psychologists have found it useful to mark such a
 distinction.[1]
 More recently, Crane (2003) calls attitudes in this broader sense
'intentional modes'. (See also Searle 1983, Chapter 1.)
These are all distinctions between aspects of mental states, where one
feature (akin to content) characterizes the subject-matter of the
mental state, and the other (akin to attitude) characterizes a mode of
entertaining it.



If experiences have contents, then they will be structured by attitude
and content: the experiences will have content in an experiential way.
Several substantive questions arise about what experiential attitudes
are.



First, it is an open question how finely grained the experiential
attitudes may be. A natural proposal is that there are different
experiential ways of having content corresponding to the different
sense modalities. But it is far from given that the modalities mark
out natural kinds of sensory experience, let alone the only natural
kinds of such experience, since it is a complicated question how to
distinguish the different kinds of sensory experience from one
another. Furthermore, there are multi-sensory phenomena, such as
synesthesia, which defy straightforward categorization as a single
kind of sensory experience. Another problem case may be the experience
of bodily actions, in which (say) visual, kinesthetic and tactile
experiences are intertwined. (See Press *et al*. 2004, Kennett
*et al*. 2001 and Fotopoulou *et al*. 2009 for
discussion of cases in which visual experience enhances tactile acuity
and kinesthetic experience generally).



Second, it is a substantive question what constitutes an
*experiential* way of having content. Tye (1995, 2000) has
proposed that what makes a state have a content in the experiential
way is that it has a certain functional role: it is
'poised' for a certain kind of use in the cognitive
system; and in addition it has non-conceptual content (see
 Section 6.2)
 and is not individuated by any objects that it may represent. Another
option is that what makes a state have content in an experiential way
is that it has the appropriate sort of phenomenology (see Chalmers
2004). A third option is that the experiential way of entertaining
content overlaps with the belief way of entertaining it--whatever
exactly that is. This last option seems to underlie a very influential
idea developed in Armstrong and Pitcher's proposals, that
experiences are belief-like in an important way. (Cf.
Pendelbury's discussion of sensuous belief in his 1986;
Heck's discussion of 'assertoric force' in his 2000;
Martin's discussion of 'coerciveness' in his 2002).
These options are not exclusive.



Third, it is a substantive question to what extent attitude and
content are independent from one another. Once we fix on an
experiential way of entertaining content, what if anything limits the
range of contents that can be entertained in that way? Going in the
other direction, once we fix on a content, are there limits on what
attitudes may be taken toward it? How this question is answered bears
on several neighboring issues. If any content that can be entertained
experientially can also be entertained unconsciously, then it will not
be contents alone that give an experience its phenomenality. The
question also bears on the question of whether there is
*non-conceptual content* (see
 Section 6.2
 and the entry on
 non-conceptual content).



Fourth, it is sometimes assumed that if experiences are structured by
attitude and content, then experience types will be individuated by
their specific attitude plus their contents, so that if an experience
*E*1 with content *C* is type-identical to an
experience *E*2, then *E*2 will
also have content *C*, and *E*1 and
*E*2 will instantiate the same experiential
attitude. The source of this idea may be an analogous claim about
beliefs: namely, the claim that if belief *B*1 with
content *C* is the same belief-type as *B*2,
then *B*2 will also have content *C*.
However, it should not be taken as a consequence of the claim that
experiences have content that their contents individuate
experience-types. Rather, this is a substantive claim that needs both
refinement and defense. Even if beliefs were individuated by their
contents, that would not suffice to show that experiences are as well.
Some additional reason would be needed to think that experiences and
beliefs are alike in this respect.



If one holds that experiences are not constitutively linked to beliefs
but are similarly structured by attitude and content, then this is one
motivation for thinking there are experiential attitudes distinct from
belief. However, one could hold that experiences are so structured (by
attitude and content), while also holding that experiences have their
contents in virtue of their connections to beliefs.


## 3. Varieties of Content



So far, we've reviewed two broad ways of developing the idea
that experiences have accuracy conditions: on the first way, these
derive from the contents of beliefs; on the second way, they
don't. On either of these two approaches, the question arises of
what kinds of content experiential contents are.



Whichever of the two approaches are taken, a basic constraint on the
contents of an experience is that these should reflect (at least some)
intuitions about when experiences are accurate or inaccurate. Another
commonly-held constraint is that the contents must be adequate to its
phenomenology: any proposal for what contents a given experience has
must in some way reflect the phenomenology of the experience. The
notion of phenomenal adequacy has considerable intuitive force.
Theories of the contents of experience are often defended on the
grounds that they "do justice to the phenomenology" (for
example, see the discussion in
 Section 6.2
 of the 'richness' motivation for non-conceptual content,
the discussion in
 Section 3.4
 of indexical content, and Chalmers (2006)) or are criticized on the
grounds that they "get the phenomenology wrong" (e.g.,
Smith 2003, 259ff; Dainton 2000, 115; Johnston 2004, 120). These
appeals presuppose that the contents of experience have to in some way
reflect the phenomenology of the experience. 



This section reviews the main theories of what kinds of contents
experience contents are.


### 3.1 Russellian Contents



Some philosophers of language defend the view that an utterance of the
form '*N* is *F*', where
'*N*' is an ordinary proper name, expresses a
structured propositional content consisting of the referent of the
name '*N*' and the property expressed by the
predicate '*F*'. For instance, if the sentence
uttered is 'Frida is cold', then the associated content
would consist in Frida herself and the property of being cold.
Contents consisting of referents of singular terms and properties
expressed by predicates are known as *Russellian*, because at
one time Russell advocated the view that singular terms contribute
only their referents to the proposition expressed by sentences in
which they occur (or utterances of such sentences). Our example uses
the ordinary proper name 'Frida'; but Russell himself
thought that such names were not genuine singular terms, and denied
that public objects ever got into Russellian contents. In contemporary
discussions, such contents are also called *singular* contents,
because they include the referent of a singular term itself rather
than a description that picks out different objects depending on which
thing in the world satisfies it.



One of the simplest theories of the contents of experiences says that
experiences have contents that are Russellian, and that these contents
consist of the very things that appear to have certain properties and
the very properties that they appear to have. For instance, if one has
a visual experience representing a red cube, the contents of
experience on this view would be the structured proposition containing
the object one sees that looks like a red cube and the property of
being a red cube. This content would have the form
[*o*,*P*], where *o* is the very object one is
perceiving in having the experience, and *P* is the property
that *o* appears to have. Note that this is a view both about
the nature of the contents themselves, and about the conditions under
which such experiences have them: an experience has such contents when
the subject is *seeing* an individual that appears to have the
property that occurs in the content.



The strongest Russellian contents include both objects and properties.
In practice, the Russellian content of a complex visual experience
might involve a number of different objects having a conjunction of
different properties: location properties, shape properties, color
properties, and so on.



Instead of strongly Russellian contents just described, one could
define weaker Russellian contents that involve the very properties
things appear to have, but don't involve the very objects that
appear to have them. These weaker Russellian contents are said to be
*existentially quantified* contents, which would be naturally
expressed by saying something of the form 'There is a red cube
at location *L*'. Most philosophers who defend the view
that experiences have Russellian contents hold that these contents are
weaker Russellian contents. (For general discussion, see Chalmers
2004; for discussion of the case of color, see Thau 2002, Shoemaker
1990, 1994, 2005, Holman 2002, Maund 1995, Wright 2003.) One reason
for weakening contents is this way is to respect the ideas that two
experiences can represent the world as being the same way, even if
they are experiences of perceiving numerically different objects, such
as twins. Another reason sometimes given for positing weak as opposed
to strong Russellian contents is that two experiences can represent
the world as being the same way, even if one is a hallucination in
which no object is perceived at all. (see e.g., Tye 1995, chapter 5,
and Tye 2000, chapter 3). Here, though, it is important to distinguish
the view that contents are individuated by the objects they comprise,
from the view that an experience has a Russellian content that
includes the object o only if the subject is perceiving the o. This
latter view is an optional extra (built in to the simple Russellian
view discussed above), not entailed by the claim that experience has
Russellian content. (Logical space has room for the view that
hallucinations can sometimes have strong Russellian contents, as when
one hallucinates one's father, or some other particular person.
For discussion of this issue see McLaughlin 1989, Smith 2002, ch. 7
and Johnston 2004).



Some philosophers have argued that experiences can't have
color-involving Russellian contents and can't have
location-involving contents on the grounds that this would allow
phenomenally different experiences of colors and locations to have the
same Russellian contents. These criticisms illustrate the appeal to
the phenomenal adequacy constraint on contents. More exactly, they
appeal to a way of specifying that constraint by holding that when two
experiences are phenomenally the same, or are phenomenally the same in
a respect, there should be some contents that they have in common.
These criticisms are discussed in
 Section 4.1
 (color) and
 Section 4.2
 (location).


### 3.2 Possible-Worlds Content



Another simple theory says that the contents of experiences are sets
of possible worlds in which things are as they appear to be in the
experience. For instance, if one has a visual experience representing
a red cube, the contents of experience on this view would be a set of
possible worlds in which there really is a red cube in front of you.
Or perhaps they might be a set of possible worlds in which the very
cube *C* that is actually in front of you is red. The central
idea behind this view is that to represent a situation--whether
in language, in thought, or in experience--is to distinguish
between two ways the world might be: first, ways the world might be if
the situation does obtain, where these include the actual world;
second, ways the world might be if the situation does not obtain. For
instance, if a subject's experience represents that there is a
red cube in front of her, she thereby (on this general view of
representation) represents the actual world as being among the worlds
in which there is a red cube in front of her. Stalnaker (1984) and
Lewis (1986) think this view best reflects the nature of
representation. 



One potential problem with possible-worlds contents concerns
experiences that represent impossible scenes. Consider the staircase
depicted in the Escher drawing, on which one seems to be able to make
four consecutive left turns, ending where one begins, yet walking
downstairs (or upstairs) the whole time. Another example of
contradictory contents comes from the waterfall illusion, when one
looks at a stationary object after looking at a waterfall, the object
appears to move, yet appears to stay still relative to its background.
Similar illusions of movement can be achieved by looking at spirals on
paper. These experiences differ phenomenally from one another.
Moreover, although all seem to represent both that something is moving
and that the very same thing is not moving, they represent much more
specific scenes as well, and these specifics clearly differ. It seems
that possible-worlds contents could not reflect these differences.
Since the set of possible of worlds in which things are as the
experience represents them to be is the null set, the view that says
that the only contents of experience are possible worlds would posit
the same content (i.e., the null set) for all of them.


### 3.3 Fregean Contents



A third theory says that the contents of experience are composed of
*modes of presentation* of objects and properties, rather than
objects and properties themselves. The key feature of modes of
presentation, on this view, is that a single object or property can
have multiple modes of presentation. A Fregean content will be true
only if the object presented by a mode of presentation in the content
has the property (or properties) presented by a mode of presentation
in the content. (See Chalmers 2004).



The Fregean theory is motivated in part by the same considerations
that motivate analogous views in the philosophy of language. The key
sort of example in the philosophy of language involves a pair of
sentences, such as "Hesperus is the morning star" and
"Hesperus is the evening star", that are the same except
for containing different terms that refer to or denote the same thing
(both "the morning star" and "the evening
star" denote Venus). Suppose a subject rationally accepts one of
these sentences while rationally rejecting or remaining neutral on the
other. Then, it is argued, though the sentences cannot differ in their
truth-value, they must play different roles in the subject's
reasoning: for example, the subject will list Hesperus among the
heavenly bodies visible in the evening, but she won't list
Hesperus among the heavenly bodies visible in the morning. Fregean
theorists take there to be an aspect of meaning that is linked to
cognitive role in this way.



Fregean contents of experience are supposed to play the same role, and
thus are motivated by cases with the same structure. Recall our
example of two people with experiences that represent the same red
cube at the same location *L*, but from different perspectives
(Schellenberg 2018). The Fregean addresses this sort of case by
holding that the experiences contain different modes of presentation
of the cube. An example of such a view is defended in Burge
(1991).



Another example that motivates the view that experiences have Fregean
contents involves perceptual constancies. In the case of color
constancy, a table can look such a way that one would readily judge
that it is uniformly brown, even though one can discern variations in
lightness and darkness. Sometimes the variations are brought into
focus by considering how many different shades of paint one would have
to use to paint a realistic picture of the table. The central problem
these cases pose for the theory of experiential content is to say
exactly what 'lightness and darkness' are lightness and
darkness *of*: since there is a good sense in which the table
looks brown, it is not variation in the table's color; but the
variations seems nonetheless to be closely related to color. Size
constancy illustrates the same problem: a departing train does not
appear to shrink as it moves away from you; but there is something
like size (even if it is not the size of the train) that does appear
to lessen, and the problem for the theory of content is say what this
is. Accounting for the constancies is a problem for the theory of
experience content, because both the constant features and the varying
ones are reflected in phenomenology, so by the phenomenal adequacy
constraint, the contents should reflect them. The problem presented by
the constancies is to show how it is that the constant and varying
features don't conflict in such a way as to make the experience
falsidical (for having contradictory contents).



One attempt to account for the variation in these cases is to invoke
Fregean *modes of presentation* of the constant features. In
the case of color, such a Fregean proposal would say that experience
represents the brownness of the table under modes of presentation that
vary with the variations in lightness and darkness. The appeal of this
strategy is that it does not treat the constant property and varying
ones on a par: the constant feature is represented at the level of
reference; the varying features at the level of sense. The table does
not look to be both brown and shiny white or grey; it looks to be
brown, by looking shinier or brighter in some parts than it does in
others.



It should be noted that the other historically influential attempts to
account for the constancies was the sense-datum theory, which (in the
case of the table) would posit a sense-datum that really is shiny and
white, in addition to the brown table itself. The Fregean attempt
claims to acknowledge both constant and varying features, without
positing such additional entities.



The main challenges for Fregean views (of utterance content, belief
content, and experience content) is to make precise in each case what
modes of presentation are such that they can reflect these variations.
(For criticisms of Fregean views about the contents of both beliefs
and experiences, see Thau 2002, ch. 2. For defense of the Fregean view
drawing on epistemological considerations, see Silins 2011). 



### 3.4 Indexical Contents



Many contentful experiences seem to have contents that must be
specified by the use of *indexical* expressions, such as
'over there', 'to the left',
'here', 'in front of/behind me', 'just a
second ago', 'since a few second ago', and so on.
For instance, some auditory experiences seem to present sounds as
coming from a direction relative to the ears; some proprioceptive
experiences seem to present pressure sensations as located in specific
parts of the body; visual experiences seem to present things in
locations relative to the eyes and the rest of the body. More
generally, contentful experiences present the world from the
subject's perspective both in space and in time. If one tried to
characterize the perspective aspect of contents in language, it would
be natural to use indexical expressions for spatial properties, for
the subject herself, and for times.



To begin with spatial content, suppose you hear a sound as coming from
your left. Someone else facing you, due to different orientation,
hears the same sound as coming from the right. Moreover, a third
perceiver situated halfway around the world could hear a qualitatively
identical sound as coming from *her* left. The area to the
first perceiver's left is the very same spot as the area to the
second perceiver's right, whereas the area to the left of the
third perceiver, who is very far away from the other two, is a
completely different part of space. Now, if contents are to reflect
which side of the perceiver the sound *seems* to come from,
then it is not enough simply to include the very area from which
sounds are coming in the content. That would not reflect what's
in common between you and the third perceiver, who is halfway around
the world. It would also fail to reflect what's different
between you and the second perceiver, who is differently oriented than
you. So it seems that some more specific representation of location
and direction is needed.



If locations and directions are represented in experience, then it
seems they are represented relative to the subject, in which case
there has to be some way of representing the subject herself (or
itself)--or at least the perceptual organs or body parts that are
on the subject-side of the spatial relations. This suggests that
bodily awareness of some sort may be involved in contentful
experiences, even when those experiences are otherwise visual or
auditory, so that experiential attitudes may have to be cross-modal,
rather than being individuated simply by sensory modality. Another
question is how self-representation works in experience. Some forms of
self-awareness are cognitively demanding; yet representation of
perceiver-relative locations and directions are clearly involved in
experiential contents. There is a theoretical need, then, for an
account of self-representations that could be had by cognitively
primitive creatures, such as animals and human infants (for
discussion, see Peacocke 1994).



Peacocke has argued (1992 chapter 3) that to adequately reflect the
spatial and first-personal perspectives in experience, a special kind
of content is needed. He calls his sort of content *scenario
content*. Scenario contents are ways of filling out the space
around the perceiver, consistent with the experience being correct.
They include a point of origin and orientation on axes, in relation to
which things are located. In our example, the sound comes from the
left, relative to the origin in the subject's body, which
Peacocke proposes is the middle of the chest.



Indexical contents (spatial, first-personal and temporal) require
modification or further specification of all three views about the
contents of experience mentioned so far. In the case of possible-world
contents, one way to have such an axis is to appeal to centered
possible worlds: worlds centered on a subject, and possibly also a
time and/or a location. The further features of the worlds can then be
specified in relation to the point of origin: in the example, coming
from the left of the center (or being such-and-such distance and
direction from it). (See discussion of Peacocke's
'positioned scenarios' in his 1992 ch. 3 and below.)



Somewhat similarly, Russellian contents may be modified in order to
reflect first-personal indexical contents by introducing contents that
are akin to open sentences, with a gap in place of a component
corresponding to the subject. In the example involving the red cube,
the contents might be something like a structured proposition
containing the cube, the non-locational properties it appears to have
(e.g., being red, being cubical, and so on), and then a component
expressed by 'two feet in front of \_\_\_\_', where the gap
can be filled in with different subjects in different circumstances.
To assess this special semantic entity for accuracy, the gap would
need to have a value. Whether its gap is filled or not, this entity is
something that in principle two experiences had by different subjects
could share. For discussion of these contents for experience, see Bach
1997 (in the Other Internet Resources section below); for a Fregean
version of gappy contents see Burge 1991 and Schellenberg 2010; for a
Russellian version of gappy contents for belief and utterances, see
Braun 1993.



How to treat indexicality is one of the main challenges to Fregean
contents of utterances as Frege himself understood these. (See Perry
1977, Evans 1990, Burge 1991.) One of the roles of modes of
presentation according to Frege was to determine reference, so that
any two expressions (or occurrences thereof) with the same sense would
have the same reference. Another role is to reflect cognitive
significance of sentences such as "Now it is 5pm, October 1st
2005". The occurrence of "now" and of "5pm
October 1st 2005" seem to refer to the same time, yet an
utterance of the sentence could be informative to someone who did not
know the date and time. One and the same time seems in some intuitive
sense to have different 'modes of presentation': one
expressed by 'now', the other expressed by '5pm
October 1st 2005'.



In the case of indexical expressions, it is hard to see what feature
of the meaning of 'now', if any, plays both of these two
roles. This poses a problem for the Fregean doctrine of senses. Later
theorists have rejected the feature of sense or modes of presentation
whereby they determine reference, while retaining the idea a single
object or property can have multiple modes of presentation. (See
Chalmers 2002). In rejecting the idea that modes of presentation
determine referents by themselves, they say that reference is
determined by mode of presentation plus select facts about the
environment in which the utterance or experience are had.



Proponents of these new Fregean modes of presentation invoke them to
account for indexical features of experience contents. In the example
of sounds coming from one's left, the new Fregeans about
experience contents invoke a mode of presentation that is shared by
the experiences of the two perceivers in different places who hear the
sound coming from their left, and a different mode of presentation for
the experience of the perceiver who hears the sound as coming from the
right. The former mode of presentation (roughly the same, they would
say, as the mode of presentation associated with the expression
'to the left') refers to different places for each
perceiver. The latter mode of presentation (roughly the same, they
would say, as the mode of presentation had by the expression 'to
the right'), when it's in the contents of the experience
of the perceiver who hears the sound coming from the right, refers to
the same place as the mode of presentation 'to the left'
when it is in the contents of the experience of the original
perceiver.



Modifications would also be needed for Russellian, possible-worlds, or
Fregean contents of *beliefs*; and proponents of each of these
views have discussed what those might be in the case of belief. (For
discussion of indexicals and Russellian contents, see Kaplan 1977,
Schiffer 1981, Austin 1990, and the entry on
 indexicals;
 for discussion of indexicals and possible-worlds content, see
Stalnaker 1981; for discussion of indexical beliefs and Fregean
contents, see Perry 1977; Evans 1981, McDowell 1984.) It is an open
question whether modifications that succeed for the case of belief can
also succeed for the case of experience. An influential approach that
has been developed for both beliefs and experiences appeals to a
special kind of possible world: centered worlds, where these are
possible worlds marked with a designated subject and perhaps a
designated time or other parameters. The centered-world framework can
provide a level of content that can be shared by two perceivers who
perceive qualitatively identical but numerically distinct cubes in
different locations as being nearby: each experience is true in worlds
where there is a cube nearby the designated center of that world.
Features such as *being nearby the center* are called
"centering features" (see Egan 2006a, 2006b, 2010), and
can be used to describe both the phenomena that indexicals are apt for
describing, as well as perceptual constancies and secondary qualities.
For discussion see Brogaard 2010 and 2018, Chalmers 2006, Egan 2006a,
2006b, 2010, GReenberg 2018. Centered worlds are implicit in
Peacocke's 1992 discussion of scenario content.


### 3.5 Multiple Contents



If experiences have at most only one kind of content, then there will
be a substantive debate about whether experience contents are
Russellian, unstructured, Fregean, or versions of these modified to
take account of indexicality. Three sorts of considerations are
typically invoked to decide between these: (i) which best reflect
intuitions about veridicality of experiences; (ii) which best reflect
distinctions to which experiences are sensitive; (iii) which contents
best reflect the phenomenology of experience.



Some philosophers have proposed that there are different explanatory
purposes for contents to serve, and one kind of content cannot serve
all of them. (On the general strategy of dividing contents in this way
see Fodor 1987 and White 1991.) Such philosophers think experiences
have multiple contents. One example of such a position holds that
experiences have contents that are both *conceptual* and
*non-conceptual* (for more on this distinction, see
 Section 6.2
 below. This kind of duality is explored by Reiland and Lyons 2015,
and defended by by Lyons 2005a, 2005b and Bengson, Grube and Korman
2011). Another holds that experiences have both 'gappy'
contents (somewhat akin to open sentences), but have object-involving
contents as well when the experience stands in the right causal
relations to environment (e.g., Burge 1991 and Schellenberg 2010; for
discussion, see Martin 2003). Here the idea is that the gappy content
reflects the phenomenology of the experience and the commonality in
content between indistinguishable hallucinations and
non-hallucinations, whereas the object-involving contents reflect
intuitions about accuracy conditions for experiences that are
adequately connected to the environment. A related idea is that
contents of experience include both general and object-involving
contents (Siegel 2010b).



Another example of a view positing multiple contents for multiple
explanatory purposes is Shoemaker's theory of color experience,
according to which experience represents both color properties, partly
in virtue of representing associated 'appearance
properties' (see
 Section 4.1
 for discussion). The representation of appearance properties is
supposed to explain the *phenomenal sameness* of certain
experiences with inverted qualia; whereas the representation of color
properties is supposed to underlie intuitions about the veridicality
of the experiences. (This is explained more fully in
 Section 4.1).
 A somewhat similar rationale is given for a form of
'two-dimensionalism' about experience contents, which
holds that experiences have both indexical Fregean contents, and
non-Fregean contents (either Russellian or unstructured) determined by
the Fregean contents in conjunction with select facts about the
environment in which the experience is had (Chalmers 2004, Thompson
2003). The indexical Fregean contents are supposed to reflect the
inferential role and phenomenology of experience, while the
non-Fregean contents are supposed to reflect the properties that we
take experiences to attribute to objects. A related two-dimensionalist
position (Chalmers 2006) adds a third kind of Russellian content to
experience, 'Edenic' content, involving special
non-instantiated 'Edenic' properties, which are supposed
to reflect phenomenology perfectly--unlike indexical Fregean
content, which is supposed to reflect it only imperfectly.


## 4. The Representation of Properties



If experiences have accuracy conditions, then it is natural to think
of those conditions as conditions under which certain *objects*
have certain *properties*. For instance, experiences seem to
attribute properties to ordinary objects such as people, fish,
bottles, shoes and the like: the bottle feels round to haptic touch;
the shoes make clicking sounds as they hit the floor; a person's
face looks to be only 3 feet away and angry; the fish smells and
tastes fishy. Taking 'object' in a broader sense, the
attribution of properties to objects seems even more widespread:
auditory experience can present *sounds* as loud;
proprioception can present *pains* as throbbing; kinesthetic
experience can present *one's toes* as cold and wiggling;
visual experience can present *an entire expanse* as bright
pink; haptic-tactile experience can present *a surface* as
smooth. Contents of experience, then, often seem to have a predicative
structure, involving objects (in either narrow or broad senses) and
properties. It then seems possible to theorize separately about the
accuracy conditions that concern the *properties* things appear
to have, on the one hand; and the accuracy conditions that concern the
*objects* or things that appear to have the properties. The
rest of section 4 will focus on accuracy conditions associated with
properties; accuracy conditions associated with objects will be
discussed in
 Section 5.



When the accuracy-conditions of an experience require that a certain
property is instantiated, the experience represents that property. For
instance, if the experience one has when seeing a grape is accurate
only if the grape is green, then the experience represents the
property of being green.


### 4.1 Which Color Properties are Represented?



The literature on how properties are represented in experience has
focused largely on the case of visual experience and color properties.
The question of how color is represented in experience is a good case
with which to review debates about what sorts of contents experiences
have. But one should generalize from the case of color experience with
caution: views that seem strongest for the case of color properties
may seem weaker for cases of other properties; views that seem
strongest for the case of visual experience may seem weaker for other
modalities, or for combinations of modalities.



The central issue here--which color-related properties are
represented in experience--is closely tied up with the more
general question of how the phenomenology of experience relates to its
having contents. These more general issues are discussed in
 Section 7;
 but because the general discussion to date has focused so narrowly on
color and visual experience, the considerations overlap greatly.



It is widely held that visual experiences represent color properties,
attributing them to objects, surfaces, volumes and locations. However,
there is substantial debate about what experiences represent when they
represent colors. Let *R*-experiences be experiences with
phenomenal character *R*, where *R* is the phenomenal
character that normal perceivers have when they see red things. Let
*G*-experiences be experiences with phenomenal character
*G*, where G is the phenomenal character that normal perceivers
have when they see green things.



According to a simple theory, *G* experiences represents
greenness, and *R* experiences represent redness. An objection
to this theory arises from a putative case of *inverted qualia
without illusion*. The case goes like this. One perceiver, call
her Nonvert, typically has *R*-experiences when she veridically
perceives and is in causal contact with red things, and she typically
has *G*-experiences when she veridically perceives and is in
causal contact with green things. Another perceiver, call him Invert,
typically has *R*-experiences when he veridically perceives and
is in causal contact with green things, and has *G*-experiences
when he veridically perceives and is in causal contact with red
things. So, in the thought experiment, when Invert, with his
*G*-experiences, sees a red tomato, his experience represents
redness; when Nonvert sees the same tomato with his
*R*-experiences, his experiences also represents redness.



On the assumption that experiences with the same color phenomenology
will have the same color content, this thought experiment challenges
the simple theory we began with, since it purports to describe a case
in which a G-experience is an experience of veridically seeing red.
Defenders of the simple theory may reject the assumption.
Alternatively, they may challenge the part of the thought experiment
that purports to describe inverted qualia *without illusion*.
That is, they may challenge the idea that Invert's
*G*-experiences veridically represent redness, rather than
non-veridically representing greenness. In response to this challenge,
most interpretations of this thought experiment build in substantive
assumptions about what sorts of conditions are sufficient for making
it the case that experiences represent one color property rather than
another. It is standardly said that the phenomenally different color
experiences come to represent the same property due to
*externalism* about color contents of experience, whereby when
a type of experience stands in the right sort of causal relations to,
say, redness, this suffices to make experiences of that type represent
redness.



If the thought experiment describes a genuine possibility, there are
at least three ways to modify the simple view: (i) Deny that content
supervenes on phenomenology, allowing that two experience with the
same color phenomenology can nonetheless differ in content. One
version of this response says that the phenomenal difference is a
'raw feel' or 'qualia' (see Block 1990, 1996);
another version holds that a single color property can present itself
to a perceiver in phenomenally different ways. (ii) Hold that there
are phenomenal differences between *G*-experiences that
represent redness and *G*-experiences that represent greenness,
so that '*G*-experience' does not pick out a fully
determinate phenomenal type An example of this response is
*externalism about phenomenology*, defended by Lycan 2001 and
Dretske 1995. (iii) Hold that there are contents shared by
*G*-experiences that represent redness and
*G*-experiences that represent greenness. This response is
developed by Thau 2002, who offers a Russellian version of it;
Chalmers 2004, who offers a Fregean version of it; and Shoemaker 1994,
2005, who offers another Russellian version of it.



Responses (i) and (ii) will be discussed in
 Section 7.
 Regarding response (iii), one Fregean theory about this thought
experiment is that it is a case in which the experiences of Invert and
Nonvert have different modes of presentation of the same color
property (say, redness). On this view, redness would be presented in
Invert's experience under a *G*-mode, and it would be
presented in Nonvert's experience under a *R*-mode, so
that the phenomenal difference between Invert and Nonvert's
experience would also be a difference in Fregean content.



A Russellian theory is that in addition to color properties, Invert
and Nonvert's experiences of the red tomato also represent a
property closely associated with redness but distinct from it, and is
represented by and only by *R*-experiences. Shoemaker calls
these properties 'appearance properties'. Call this the
*Shoemaker* proposal. (Shoemaker 1994, Thau 2002, though Thau
denies that colors are represented in experience, claiming that only
the other properties are--so he does not accept the thought
experiment exactly as stated. For another denial that colors are
represented in experiences see Tolliver 1994).



A final theory about this thought experiment combines aspects of the
Fregean and Russellian proposals. It says that Invert's and
Nonvert's experience each has two contents associated with it.
One set of contents involves objects and properties represented by the
experiences; the other involves modes of presentation of these objects
and properties. On this proposal, the object-property contents
associated with Invert's experiences are the same as
Nonvert's, but their modes of presentation are different.



The issue between the Fregean and Shoemaker proposals is subtle. Both
agree (contrary to response (i), which includes the qualia view) that
the difference between Invert and Nonvert's experience of
redness is a representational difference of some sort, as opposed to a
raw feel. And both views posit entities associated with this
difference: appearance properties for the Shoemaker proposal; modes of
presentation for the Fregean proposal. The difference concerns the
status of the entities associated with yet distinct from color
properties: are they modes of presentation of the colors, or are they
simply other properties, represented alongside the colors (or instead
of them, as Thau holds). In Shoemaker's 1994 version, color
properties are represented in experience *by* representing
appearance properties. The issue is sometimes described by saying that
the Shoemaker proposal predicts that there are *two*
color-associated ways that the tomato looks to be to each perceiver:
it looks to be red; and it looks to have the appearance property. In
contrast, the Fregean view predicts that there is just one
color-associated way that the tomato looks to be: it simply looks to
be red.



A related question is which properties color experience represents
things as having when it represents them as being colored. Since color
experiences in principle could be systematically in error, this is
distinct from the ontological question of which properties the colors
are, though the same options suggest themselves. According to one
position, when an experience represents that an apple is red, it
represents that it has a disposition to cause certain kinds of
experiences. (See Langsam 2000 and McDowell 1985) According to an
opposed position, when an experience represents that an apple is red,
it represents that it has a non-dispositional property (McGinn 1983,
Johnston 1992, Boghossian and Velleman 1992). One version of the
latter says that experience represents a primitive property that
cannot be specified in non-chromatic terms (Broackes 1992, Campbell
2003). Yet another says experience is neutral on whether redness is or
isn't primitive. (Byrne and Hilbert 2003) Another question is
whether colors are represented as being properties of external
objects, or of sense-data (where these are private mental objects), or
both.


### 4.2 Which Spatial Properties are Represented?



Many contentful experiences represent properties as being instantiated
at certain locations: one hears sounds as coming from certain
directions; one experiences pains in specific parts of the body; one
sees different colors in different places in the scene before the
eyes. It is more controversial whether gustatory and olfactory
experiences represent locations. We certainly end up attributing
tastes and odors to things in the external world, but this alone does
not show that the associated experiences represent any locations. (For
discussion of olfactory experience see Lycan 2000, Smith 2002, ch 5,
Batty 2010, Richardson 2013, Coveden-Taylor 2018; for discussion of
gustatory experience see Smith *ibid*.) How are locations
represented in experience, when they are?



One debate about the nature of representation of space concerns
whether the positional properties represented in visual experience are
relational or monadic. For discussion, see Casullo 1986.



A different debate concerns which contents are best to reflect
important similarities in spatial experiences. Consider an experience
whose contents include those that are expressed by an utterance of
'There is a red cube at location L'. A simple view is that
nothing more finely grained than location *L* itself is
included in these contents. Peacocke (in his 1992, chapter 3)
criticizes this view. Suppose that the experience in the example is
veridical, so that there really is a red cube at *L*, And
suppose *L* is to the left of the original perceiver, but that
there is a second perceiver who is seeing the same red cube, except
given her position relative to the cube it is on her right. The
experiences differ: the perceivers see the cube as being in different
positions relative to their bodies, and the experiences will affect
actions of the perceivers differently, in that one would have to move
to her right while the other will move to her left to get to the cube.
Going with these differences, there seems to be a phenomenal
difference between the experience of seeing a red cube to your left
and seeing a red cube to your right. If the contents of experience are
to reflect such differences, then there must be some more specific
representation of location *L* than is allowed by simply
including the area itself in the contents. The potential problem
discussed here for location suggests that the contents of experience
include indexical contents of some sort.



Peacocke has argued *scenario contents* are needed to
adequately reflect how locations are represented in experience. A
*scenario* is a spatial type, with a fixed origin in the human
body and axes given by directions front/back, left/right, and up/down.
Once the origin and axes are fixed, the scenario specifies the way the
space is filled in at each point-type identified by its distance and
direction from the origin. A *positioned scenario* is a
scenario that has specific origin and axes at a specific time, and is
thus assessable for accuracy. Positioned scenarios are supposed to
reflect the way in which locations are represented in experience.



According to another proposal about spatial experiences, made by
Cussins (1990), experiences of space consist in the subject's
having abilities to move in certain ways. On this view, to experience
a sound as coming from the left is to know how to locate the place it
is coming from, where this knowledge is practical knowledge about how
to move through the environment. Having these abilities, according to
Cussins, enables the subject to form beliefs and other mental states
that are assessable for accuracy (or that have contents in our sense);
but the abilities themselves, which are supposed to constitute
experiences, are not; and even a creature who hadn't yet or
couldn't form such states could still have the abilities. To
have the abilities, according to Cussins, is to be presented with
locations in experience. In his 1990 he calls this way of being
presented with locations *construction-theoretic* content
(where this kind of 'content' is not assessable for
truth).



Peacocke has objected to Cussins' construction-theoretic content
that there appear to be cases where subjects lack the abilities to
move to the locations presented in experience, for instance due to
paralysis. Whether this objection has force depends on the notion of
'abilities'; one might think the paralyzed have abilities
that they can't exercise.



Peacocke's and Cussins' theories differ in that scenario
contents are assessable for accuracy and construction-theoretic
contents aren't, and both purport to be contents of the same
experiences. However, something like construction-theoretic contents
can be combined with scenario contents. One outstanding question for
Peacocke's theory is how an experience comes to have scenario
contents, and a potential answer to this is that an experience comes
to have the scenario contents it does by the subject's having
the abilities Cussins describes. More generally, the question of what
makes it the case that one has the experience contents one does is an
outstanding question for many theories of content (this issue is
discussed further in the
 Section 8).



Another debate about the representation of spatial properties concerns
the phenomenal difference between the experiences of seeing a
four-sided equilateral figure as a square and seeing it as a regular
diamond. (The example is from Mach 1914).



> 
> ![Image 1](image1.jpg)
>   
> 
> 



In one version of this contrast, there are two figures differing only
in their orientation to the viewer (on a page, the top and bottom of
the square is parallel with the top and bottom of the page; while the
diamond is just like the square except rotated 45 degrees around its
center.) Assuming that the property of being a square is the same as
the property of being a regular diamond (an assumption defended by
Peacocke in 1993, contested by Tye 2003, but granted by Tye 2004),
this appears to be a case in which there is a phenomenal difference
without any difference in the properties represented. The options,
then, are similar to the ones listed in the discussion of the inverted
color qualia: (i) deny that there is a difference in content
corresponding to the phenomenal difference; (ii) hold that there are
differences in the *way* the property of being square is
represented, i.e., invoke different modes of presentation of this
property (Peacocke 2001a, 2001b); (iii) find some other property that
is represented in one experience but not the other, such as the
viewer-relative property of resting on a side, or the property having
two horizontal sides (properties allegedly attributed by experience to
the square but not the diamond); and the property of standing on a
point or the property of having inclined sides (properties allegedly
attributed by the experience to the diamond but not to the square)
(Tye 2005). Here we have another case of a debate between Fregean and
Russellian positions on the nature of experience content.



Another topic concerning spatial representation in experience is the
relation between representing locations of things, on the one hand,
and representing things as mind-independent, on the other. According
to some philosophers, for the case of visual experience, representing
things as occupying three dimensions of space suffices for
representing them as mind-independent (see Strawson 1958, Peacocke
1983, Masrour 2011; for dissent, see Smith ch 5, and 2000). According
to others, visual experience represents spatial locations as locations
from which one could act (Schellenberg 2007).
 [2]



### 4.3 Are High-Level Properties Represented?



Positions on which properties are represented in experience can be
located on a rough continuum, with low-level properties (where these
include color, shape, illumination, and depth) at one end, and
high-level properties (where these include kind properties, agential
or other emotional properties, and semantic properties) at the other.
The issue is which of these properties can be perceived as being
instantiated: e.g., whether one can have a visual experience that
represents that someone is *trying* to do something. The debate
about this is closely related to the earlier debate in the philosophy
of science about whether one can distinguish between observational and
theoretical properties (see Introduction to Suppe (1979)). In the
philosophy of mind, defenders of the view that only low-level
properties are represented in experience include Tye 1995, Dretske
1995, Clark 2000, Price 2009, Brogaard 2013, Bryne 2017; defenders of
the view that high-level properties are represented in experience
include Peacocke 1992, Siewert 1998, Bayne 2009, Masrour 2011, Nanay
2011, Block 2014, Siegel 2006 and 2017). It is worth noting that
analogous debates can be pursued for views of experience that deny
that experiences have accuracy conditions: for instance, if (with
naive realism of the sort championed by Martin) one thinks that
veridical experiences consist in being perceptually presented with an
object and its properties, the debate will concern which properties of
objects one can be perceptually presented with; if one is a pure
sense-datum theorist, the debate will concern which properties
sense-data can have.



According to one type of argument that high-level properties can be
represented in experience, experiences can be theory-laden, in the
sense that being disposed to recognize an object or property
influences the phenomenology and content of the experience. The main
premise of the argument is a claim about phenomenology: a place, such
as your neighborhood, or a person, such as a close friend, may look
different to you than it did when you first saw them (these examples
are discussed by Siewert 1998); written text and spoken words in an
initially unfamiliar language may look and sound different before and
after you come to know their meaning (the auditory example is
discussed by Peacocke and Siegel). These are cases in which background
knowledge or abilities putatively influences what is represented in
experience. If this can happen, then even if a distinction in the
philosophy of science between 'observation and
'theory' can be drawn, it will not align with the
representation of low-level properties, on the one hand, and
high-level properties on the other.



One type of case for denying that high-level properties are
represented in visual experience appeals to two main ideas. First,
that the only experiential representations are those that result in a
lawlike way from retinal stimulation. Second, retinal stimulation, in
turn, is said to give rise to experiences independently of other
cognitive apparatus on the part of the subject, and is insulated from
any information processed cognitively. A case of this sort is given by
O'Shaughnessy (2000), chapter 17.



Some debates about which properties can be represented in perception
focus on specific properties. It is important to distinguish between,
first, *perceiving* causation, on the one hand, and, second,
representing causal relations in experience, on the other. It is a
substantive question whether the former can happen only if the latter
does. The first issue concerns whether one can perceive causation, or
whether all one can perceive is a sequence of events, minus its causal
nature (assuming there is such a thing). For discussion see Ducasse
1965, Armstrong 1997, Fales 1990, Pietroski 2000, Beebee 2003,
Butterfill 2011. For discussion in psychology of cognition regarding
causation, see Michotte (1963) and essays in Premack, Premack and
Sperber (1995.) The second issue concerns whether experiences can
represent causal relations, in the same way they represent colors,
shapes and whatever else is plausibly represented in experience.



Another example of this sort of debate concerns absences. As before,
one can distinguish the question whether you perceive that something
is absent, from the question whether absences can be represented in
experience. Putative examples of perceiving absences include hearing
pauses, sensing the emptiness of your stomach, seeing the total
darkness of a cave, or feeling the holes in old-fashioned computer
paper by running your finger down the sides of the page (these
examples are from Sorensen 2004; see also Sartre 1958 and Farennikova
2013 and 2015). Another putative example comes from Taylor (1952),
which contains a diagram consisting of two circles, one with a dot in
it, the other empty. Arguably, you can see that there is no dot in the
empty one; this is a putative example of seeing that a dot is absent
from the empty circle, once one is primed to see the absence by seeing
the dotted circle next to the empty one. This interacts with
discussions of the role of causation in seeing (for discussion of the
role of causation in perception, see entry on the causation and
perception). Turning to questions about whether absences are
represented in experience, one question is whether the absence of some
particular thing, or of some kind of thing, can be represented in any
kind of experience. Perhaps one could represent (or, if one is
fortunate, misrepresent) that one's limb is missing, or that no
one is home. Some phenomena involving absences may be tough to
categorize. For instance, if, while seeing the empty circle, by some
non-hallucinatory process you came to seem to see a dot in the circle,
would you thereby misperceive the absence of a dot as a dot? Or would
you merely falsidically represent that there is a dot in the circle?




A final example of debate concerning specific properties concerns
affordances. Affordances are possibilities of action of a creature
(Gibson 1977). Some philosophers argue that we perceive affordances
(Nanay 2011) or that affordances can be presented in visual experience
(Prosser 2011, Siegel 2014). 


## 5. How Are Objects Represented In Perception?



When properties are represented in experience, they are often
attributed to ordinary objects: for instance, one may have a visual
experience that attributes redness and sphericality to a tomato, or a
haptic tactile experience that represents smoothness and
cylindricality of a cup in one's hands, or an olfactory
experience attributing scents to flowers, or a gustatory experience
attributing deliciousness to something one is chewing. In order for
properties to be attributed to objects in experience, the object must
be represented in some way. A variety of different ways have been
proposed for the case of visual experiences, so we will focus on
these. The debate is best introduced by considering an example.



Suppose you are seeing a cube that looks red and looks to be at
location *L*. To simplify matters, let us ignore properties it
looks to have besides color and location, and let us ignore as well
all the other issues discussed about how properties including
subject-relative locations are represented in experience, in
particular whether the contents include modes of representation of
properties or properties themselves as constituents. All that matters
for this discussion is that there be some properties attributed to the
objects.


### 5.1 Object-Involving, Gappy, and Existential Contents



One proposal is that when you have this experience, you entertain
contents that have the cube itself as a constituent, and attribute to
it whatever properties the cube looks to have.



According to this proposal, when you represent an object in
experience, you entertain contents such as (1):



> 
> (1) *o is red and at L*, where *o* is the very cube that
> you see.
> 



Here, the object itself is a constituent of the content. McDowell
defends a less simple view that an object-involving Fregean sense is a
constituent of the content, rather than the object by itself. For now
it will be simplest if we focus on the simpler version.



A second proposal is a bit more complicated. On this view,
hallucinations can share the same phenomenology as cases of
object-perception, and this phenomenology suffices for the subject to
experientially entertain a special semantic entity akin to an open
sentence. This might be a thought of as a structured proposition with
the same form as (1), except that in place of the perceived object,
there is an unfilled position in a structure. This can be symbolized
as follows:



> 
> (2) \_\_\_\_\_ is a red cube at *L*.
> 



On this view, in cases of object-perception, the properties expressed
by the special semantic entity that is experientially entertained
characterizes the way the perceived object appears. It is thus written
into this proposal that the gap gets a value only in cases of
perceptual contact with an object. It thus posits multiple contents to
experience. Versions of this view have been defended by Bach 1997 (in
the Other Internet Resources section below) and Burge 1991.
Bach's proposal is closer to the one stated. Burge holds that in
place of the gap, there is a demonstrative mode of presentation of an
object. See also Schellenberg 2018, Matthen 2019.



A third proposal (a version of which is defended by McGinn 1981) is
that when you see the cube, you entertain *existentially quantified
contents*, such as (3):



> 
> (3) There is a red cube at L.
> 



Some philosophers argue against this proposal on the grounds that it
is not adequate to the phenomenology of seeing objects, wherein one
always (it is said) seems to see a particular object. The simple
existentially quantified contents, it is said, cannot reflect the
phenomenology of being visually presented with a particular object.
(For this line of criticism, see Campbell 2002 ch. 6, Soteriou 2000,
Martin 2003, Burge 1991.) Others go further and say that only contents
that could naturally be expressed using a demonstrative expression
putatively referring to the seen object will be adequate to this
phenomenology. (Campbell 2002 ch. 6)



Another consideration that has been brought to bear on the debate
about how objects are represented in experience is the predictions
that the proposals make about the accuracy (veridicality or
falsidicality) of experiences. One kind of case that brings the
different predictions into focus is a case discussed by Grice (1961).
Suppose you see a cube (Grice's example involves a pillar
instead of a cube). Unbeknownst to you, you are seeing the cube in a
mirror, so that the cube is behind you, though it looks to be at
location *L* in front of you. In addition, the cube you are
seeing is orange, though due to strange lighting it looks red. Now
suppose that behind the mirror, at the exact location where the orange
cube appears to be, there really is a red cube. The situation is then
this: there are two cubes, one orange and one red; you see the orange
one but it's not at location *L*, whereas you don't
see the red one but it is at location *L*. With respect to this
case, the view that says that objects are represented in experience
via object-property contents such as (1) will predict that your
experience is inaccurate ('falsidical'), because the cube
you see is not red and at *L*. In contrast, the simple
existentially quantified contents, (3), predict that the experience is
veridical, because the way things appear (on that view) is that there
is a red cube at *L*, and there is a red cube at *L*. If
one of these verdicts is intuitively stronger than the others, then
that counts in favor of the view(s) that predict it.



What about the gappy contents, proposal (2)? Since it is written into
the proposal that the gap gets a value when the subject of the
experience sees an object that appears to have the properties attached
to the gap, the experience in the cube case will be falsidical, since
even though there is a red cube at *l*, that cube is not the
one you see. The cube you see is not red and at *L*, so the
contents are false, hence the experience is falsidical. Soteriou
(2000) argues that this is the right verdict (intuitively, the
experience is falsidical), and so cube cases count against the
proposal (3) which predicts that the experience is veridical.



A third consideration bearing on the choice between (1), (2) and (3)
concerns phenomenal sameness. If two experiences that are phenomenally
the same have the same content, then proposal (1) will not work,
unless it is part of a more complex proposal that experiences of
seeing objects have multiple contents: gappy ones shared by
phenomenally indistinguishable experiences, and object-involving ones
that are not so shared.


### 5.2 Causal and Non-Causal Contents



Of the three proposals considered so far, the two that posit
object-involving contents ((1) and the multiple-content proposal (2))
predict that the cube experience will be falsidical. Searle (1983)
defends a fourth proposal about how objects are represented in
experience that makes the same prediction, but without positing
object-involving contents. He proposes that when you see the cube, you
experientially entertain complex contents of the following form:



> 
> (4) There is a red cube at *L*, and the fact that there is a
> red cube at *L* is causing this experience.
> 



Searle's proposal predicts that the cube experience is
falsidical, because the fact that there is a red cube at *L* is
*not* causing your experience, and the second clause of his
complex existentially quantified contents says that it is. According
to Searle, this proposal also reflects the phenomenology of
particularity.



Searle's proposal entails that in experiences of seeing objects,
the experience itself is represented (note the occurrence of
'this experience' in (4)). Armstrong, Burge, Soteriou and
others have objected to Searle's proposal on the grounds that
these contents are too cognitively sophisticated to be contents of
experiences of seeing. They argue that only sophisticated creatures
have the cognitive resources needed for this form of self-reference,
and plenty of creatures can have visual experiences of seeing objects
even while lacking these resources; so such self-reference cannot be a
necessary condition for visually experiencing objects. Another
objection, also raised by Armstrong, Burge and Soteriou, is that
causal relations between experiences and facts are not represented in
experience. Armstrong claims that this too is overly sophisticated;
Burge claims that it is not part of the phenomenology of visual
experience. The debate turns on exactly what cognitive resources are
needed for an experience to represent (a) itself, and (b) causal
relations between itself and other things. If one denies that causal
relations of any sort can be represented in experience, then one will
think Searle's view is false.



In principle several replies to these objections are open to defenders
of Searle's position. First, they can claim that what is needed
for representations of (a) and (b) is not so cognitively sophisticated
after all. Second, they can deny that the cognitively sophisticated
and cognitively unsophisticated creatures have experiences with the
same contents. Third, they can argue that such causal relations really
are present in visual phenomenology, for example by contrasting visual
experiences of seeing objects with visual experiences of imagining
them. Searle himself pursues the last strategy in his 1989.


### 5.3 Are Ordinary Objects Represented?



The discussion so far has assumed that ordinary objects are
represented in at least some experiences. Some philosophers assume
that ordinary objects are represented in visual experience, but this
is a matter of some controversy. According to theories on which visual
experience represents only very low-level properties, such as color,
the shapes of facing surfaces, their illumination properties and
nothing more, visual experience does not carry information about
whether any of the facing surfaces belong to the same ordinary object,
and does not carry information about whether there are any ordinary
objects in the immediate environment at all. Instead, visual
experience represents that low-level properties are instantiated at
certain locations, without taking a stand on whether ordinary objects
are instantiating them. A version of this view is defended by Austen
Clark (2000, ch. 5), who argues that experience represents colors (and
perhaps other low-level properties) instantiated in regions of
space-time around the perceiver, and nothing else. In Clark's
terms, reference within experience is limited to reference to places:
these are the only things to which properties are attributed in
experience. Clark refines his view in 2004.


### 5.4 Mind-Independence



Some perceptual experiences arguably represent objects as existing
independently of the subject's mind (where something is
mind-independent only if it does not depend for its existence on being
perceived). One might think that representing that something exists
independently of being perceived is a precondition for representing
the occurrence of more mundane happenings in the external world, such
as a tomato's being round, or a cat's sitting on a mat.
Representing mind-independence is thus arguably a fundamental kind of
content. In what different ways might experiences represent things as
mind-independent?



One debate in this area (already mentioned in connection with spatial
representation) is whether a visual experience's representing
things as occupying three dimensions suffices to represent things as
mind-independent (see Strawson 1958, Peacocke 1983, Smith 2002).



Another idea, prominent in the writings of Merleau-Ponty 1945 and
Husserl 1900, is that some experiences are about things in the world
external to the mind in virtue of representing possible interaction
between the subject and the thing represented. For instance, according
to one version of this view, a visual experience's representing
(say) a bird as mind-independent consists (at least in part) in its
representing that if the subject moves relative to the bird, different
parts of the bird will come into view, and that if something opaque
moves between the subject's eyes and the bird, then the bird
will be occluded. More generally, the idea is that an object looks
mind-independent if it looks as if different perspectives on it may be
taken.



It is clear that subjects have some sort of expectations to this
effect. But what concerns Merleau-Ponty and Husserl is what bearing
these expectations have on experience itself. These two philosophers
agreed that experience would not be what it is without such
expectations; but they disagreed about how exactly they are
incorporated into experience. According to Merleau-Ponty, the
'expectations' took the form of 'readiness' on
the part of the subject to move her body relative to an object in
order to get a better view, if she so wished. Rather than posit mental
*states* that represent the possibility and possible results of
such interaction, Merleau-Ponty thought that such representation was
implicit in the subject's own dispositions. This idea has been
developed in the literature on so-called 'embodied
cognition' (see Clark 1997, Hurley 2000, Noe and O'Regan
2001). Husserl, in contrast, held that the subject's
*expectations* about how phenomenology would change with
changes in the perceiver's apparent movement were presented in
experience along with other properties, such as location and shape.
Similar ideas are developed in Smith 2002 and Siegel 2006b.



A third idea in the area is that tactile experiences themselves, by
virtue of their phenomenology alone, represent things as external to
the subject's body. Consider the experience of grasping a
rounded bottle. In experiencing the limits of one's body, one
seems simultaneously to experience the surfaces of things external to
one. This seem to yield two ways of describing tactile phenomenology:
it involves both a feeling of pressure, located roughly at the places
on the hands where the glass is touching; and a feeling of something
spatially external to the body, located at the point where it touches
the body. Moreover, tactile experiences of grasping a rounded bottle
seems to represent the surfaces touching each part of the hand as
surfaces that are part of the same object, so that it is also part of
what the experience represents that the surfaces extend through space
not occupied by the body. If so, then tactile experiences represent
both happenings inside the body and things outside the body.



Now, in principle something could exist in the space outside a
subject's body, yet not exist independently of that
subject's mind. But assuming that things outside the body are
not also internal to the mind, this would be a way of representing
things outside the mind as well. For further discussion of the
relation between tactile experience and mind-independence, see
O'Shaughnessy 1989, Martin 1992b, Smith 2002, Condillac
1947.


## 6. Concepts and Content



Many philosophers hold that beliefs and *concepts* are related
in the following way: in order to have a belief that *x* is
*F*, for any object *x* and any property *F*, a
subject must have concepts of the object and the property, and must
*deploy* those concepts in the belief. When concepts and
beliefs are related in this way, belief content is said to be
*conceptual*. Call this view *belief conceptualism*
(endorsed by Dretske 1981 and Martin 1992a, among others). Belief
conceptualism is typically defended on the grounds that beliefs differ
from one another according to which concepts one has. One can believe
that whales swim without believing that large sea-dwelling mammals
swim, even though whales are large sea-dwelling mammals. According to
a common defense of belief conceptualism, the relevant beliefs differ
in which concepts the thinker is deploying, and that explains how it
is that someone can have one of these beliefs without the other.
According to a related defense of belief conceptualism, it explains
why some thinkers cannot have any thoughts about some subject matter.
Suppose the thinker lacked the concept 'whale': she had no
idea what whales were, nor even that there was such a thing. Arguably
such a thinker could not believe that whales swim, that whales are
blue, or anything else about whales. According to belief
conceptualism, this is because she lacks the concept of a whale. A
full specification of belief conceptualism would require explicating
what concepts are, and what it is to possess and deploy one.



If beliefs have conceptual content, a question arises about whether
experiences do as well. Here it is useful to distinguish between two
theses about experiences. The first concerns concepts explicitly, and
is the straightforward analog of the thesis above.



> 
> *Experience conceptualism*: For any object *x* and any
> property *F*, a subject has an experience as of *x*
> being *F* only if she has concepts of *x* and
> *F*, and deploys those concepts in the experience.
> 



The second thesis says that the contents of experiences are the same
kind of content as belief contents. This thesis does not mention
concepts explicitly.



> 
> *Same-content*: For any experience as of an object *x*
> having a property *F*, if the experience has content
> *p*, then it is possible to have a belief with content
> *p*.
> 



In principle two strands to the debate about the role of concepts in
experience contents can be distinguished: whether experiences have any
contents that cannot be believed, and whether concepts play the same
role in the contents of beliefs as they play in the contents of
experience. Some philosophers accept the same-content thesis and
belief-conceptualism but deny experience-conceptualism, e.g., Tye
(2005). Speaks (2005, 2009) defends same-content thesis but denies
experience-conceptualism.


### 6.1 Conceptualist Views of Content



Experience conceptualism and the same-content thesis go naturally with
the views (discussed in
 Section 2.2
 above) that link the content of experience to the contents of
beliefs, either by identifying experiences with beliefs or with
dispositions to form beliefs. However, McDowell (1994), Sedivy (1996)
and Brewer (1999) endorse both theses while denying that experiences
and beliefs are linked in either of these ways. They defend both
theses on the grounds that experiences can provide justification for
beliefs only if these theses are true. Peacocke (2001a), Byrne (1996),
Heck (2000) and others have objected to these 'epistemic'
defenses of experience conceptualism on the grounds that experience
can stand in inferential relations with beliefs if they have accuracy
conditions, and they can have accuracy conditions even if experience
conceptualism is false. (Earlier defenses of experience-conceptualism
are found in Craig (1976) and Peacocke (1983)).



Dretske and Martin have argued against experience conceptualism on the
grounds that it cannot reflect the *informational richness* of
experience (see Dretske 1981, Martin 1992a, see also Bermudez and
Macpherson 1999) and Chuard (2007). The main idea that experiences can
(and typically do) convey information about so many objects,
properties and relations in the environment that it is implausible to
suppose in those cases that the subject could possess and deploy
concepts for every object, property and relation that experience
represents. The richness argument thus has two main parts: the first
part defending the alleged phenomenal and informational richness of
experience; the second defending that inference from richness to the
falsity of experiential conceptualism.



Martin in his 1992a makes a version of the richness argument against
experiential conceptualism. His strategy is to consider cases in which
one remembers a perceived object or property that one did not notice
at the time of the experience itself. In Martin's example,
someone is looking for cufflinks in a drawer, and fails to see them
even though they are right there in front of him; but later on, when
remembering the look of the drawer's contents, realizes that the
cufflinks were among them. The fact (if it is a fact) that one can
have such memories suggests that the cufflinks were perceived
consciously after all.



How is this sort of case supposed to counter experiential
conceptualism? If deploying a concept of an object or property is
sufficient for noticing it, then the fact that one can perceive
something without noticing it implies that one can perceive something
without forming a concept of it. And that in turn suggests that one
can represent an object or property in experience without forming a
concept of it--contra experiential conceptualism.



Dretske develops the richness argument slightly differently. He
distinguishes between *digital* and *analog* ways of
encoding information, where the difference between these is analogous
to the difference between the way statements and pictures
(respectively) encode information. When information that *s* is
*F* is encoded in digital form (as in a sentence, for example),
no extra information is carried in the encoding; but when information
that *s* if *F* is encoded in analog form (as in a
photograph, for example), extra information will usually be carried in
the encoding. After explicating the difference between analog and
digital encodings of information, Dretske (in his 1981) writes,
"The traditional idea that knowledge, belief and thought involve
*concepts* while sensation (or sensory experience) does not is
reflected in this coding difference". Dretske thinks that
experiences encode information in the analog way, whereas beliefs
encode information in the digital way. This view targets both the
same-content thesis, and experiential conceptualism.



A different argument against experiential conceptualism appeals to the
idea that the contents of experience are sometimes very *finely
grained*. The idea here is that experiences often provide
detailed, determinate information, in contrast to thought. Consider
the case of color experience. If you have an experience as of
something red, you will experience it as being a determinate shade of
red. In contrast, if you think that something is red, there need not
be any determinate shade of red such that you think that it is that
shade of red. It is worth noting that an experience could be
finely-grained without being informationally rich--as a visual
experience would if it represented nothing but a uniform field
(sometimes called a 'ganzfeld') of a single color.



In his 1995, Tye attacks experience-conceptualism using the example of
determinate color properties, which he says can be represented in
experience even by subjects who lack concepts of them. A similar point
is made by Raffman (1995) who discusses evidence that humans
perceptually discriminate more shades of color than they remember and
have concepts of. It is supposed to be independently plausible that
the discriminated shades are represented in experience; so if the
subjects really do lack concepts of them, then experiential
conceptualism is false. A similar line of thought is hinted at by
Evans (1982), who asks (apparently rhetorically) "Do we really
understand the proposal that we have as many colour concepts as there
are shades of colour that we can sensibly discriminate?"
(229).



In response to this line of thought, McDowell (1994) has proposed that
the subjects really do possess fine-grained color concepts, albeit
*demonstrative* ones. This proposal has sparked debate about
what counts as possessing a demonstrative concept. One point of debate
concerns whether a subject counts as having a demonstrative concept of
a shade of color, only if she can re-identify the shade on subsequent
occasions. If so, then McDowell's argument fails, since this is
precisely what human subjects cannot always do. It is a matter of
controversy, however, whether having demonstrative concepts does
require this (as Kelly 2001 argues), or whether there can be one-off
demonstrative concepts. Another point of debate raised by
McDowell's concerns whether it is possible to form demonstrative
concepts of the shade represented in experience in cases of illusion,
when the shade represented in experience differs from the shade of the
thing seen. If demonstrative concepts of color shades can pick out
only shades actually had by the thing demonstrated (as Heck 2000
contends), then again McDowell's argument fails. However, it is
again a matter of controversy whether demonstrative concepts are
limited in this way. Yet another point of debate in this area is
whether experience itself would be needed to anchor demonstrative
concepts in the first place -- in which case, it is said, they
could not already be constituted by them (Heck defends this view).


### 6.2 Varieties of Non-Conceptual Content



This section reviews some proposals about the contents of experience
that use the label 'non-conceptual content'.


#### Scenario Content



One way to argue against the same-content thesis is to assume, or
independently defend, a theory of belief content, and then offer a
positive account of experience content that differs from it. This is
Peacocke's strategy in his 1992. (Note the change in view from
experiential conceptualism, which Peacocke defends in his 1983).
Peacocke accepts belief conceptualism, and has the view that belief
contents are Fregean, composed of Fregean senses. Peacocke describes a
kind of content called *scenario content* that is not composed
of Fregean senses, but is the content of experiences. Scenario content
is a set of ways of filling out the space around the perceiver,
relative to an origin and axes marking directions, that is consistent
with the perceiver's experience being veridical. Peacocke
stresses that although spatial concepts may be needed to specify a
scenario, those concepts need not be possessed by subjects whose
experiences have that scenario content. Thus, according to Peacocke,
spatial properties (such as coming from the left of the perceiver, or
being approximately three feet away) can be represented in
experiences, even when the subject lacks the concept 'to the
left' or 'being approximately three feet away'. If
experiences have scenario content, and if Peacocke is right that the
relevant concepts are not required for experiences to have scenario
content, then experience conceptualism is false (barring the necessary
accompaniment to scenario content of other contents that can be had
only if the subject possesses and deploys concepts of the very ways of
filling out the space around the perceiver that are specified by
scenario content).



According to Peacocke, one role of scenario content is to make it
possible for the subject to form demonstrative concepts, such as ones
that might naturally be expressed by *that figure*, *that
color*, *that shape*, where the figure, color or shape
picked out by the concept is one that is represented in experience.
Like demonstrative expressions, demonstrative concepts pick out
different things on different occasions, and as Peacocke sees it the
role of experience is to anchor a demonstrative concept to its
referent. Positioned scenario content is the content of experience
that does this.


#### Proto-Propositional Content



In another example involving Mach figures (discussed in
 Section 4.2),
 one focuses on a single four-sided equilateral figure, and contrasts
the experience of seeing it as a square and seeing it as a diamond.
The experiences supposedly differ phenomenally. According to Peacocke,
there can be no difference in the scenario content of these
experiences, because they represent the space around the perceiver as
filled in in the same way. Rather, according to Peacocke, the
difference is in the *way* in which the very same shape
property is represented in experience. The central claim in support of
this view is that the properties represented do not differ. In his
(2001a) Peacocke offers two other examples in support of this claim.
First, there are supposedly two ways of hearing the interval that
sounds when middle C and F-sharp just above it are played on a piano:
one and the same interval, he says, can be heard as an augmented
fourth, or as a diminished fifth. Second, a matrix of evenly spaced
dots can be seen as a set of rows or a set of columns.



> 
> ![Image 2](image2.jpg)
> 



The multiple 'ways' in which the same property can be
represented, according to Peacocke, are not modes of presentation of
the sort that constitute the contents of beliefs. In the three
putative examples of single properties that are represented in
different ways (the four-sided figure, the middle C/F-sharp interval,
and the arrangement of dots), there are (according to Peacocke)
multiple concepts in the vicinity that pick out the same shape,
interval, or arrangement. The concepts 'regular diamond'
and 'regular square', or simply two occurrences of
'that shape', one for each way of seeing the four-sided
figure; the concepts 'augmented fourth' and
'diminished fifth' in the case of the interval; and the
concepts 'row' and 'column' in the case of the
dots. These concepts differ from the perceptual 'ways' of
representing the shape (or the interval or the dot-arrangement),
according to Peacocke, in that the perceptual 'ways' make
it possible to acquire the concepts, and so cannot be identical with
them. In the case of the two demonstrative shape concepts, these are
anchored to each shape by the experience of it, and in order to play
this role, they cannot be the same as demonstrative concepts (a point
echoed by Heck). In his (1992), Peacocke uses the label
'proto-propositional content' for contents just described.
The discussion of these examples in his (2001) is intended to clarify
the 1992 discussion (see 2001, fn 14).


#### The State View



According to the *state view*, an experience *E* has
non-conceptual content just in case (i) *E* has accuracy
conditions; and (ii) the subject of *E* need not possess any of
the concepts used to specify *E*'s correctness
conditions. This thesis that experiences have non-conceptual content
in this sense is sometimes called the *state view* of
non-conceptual content (Heck 2000), because it is only a condition on
the possession of concepts, rather than being a condition on the kind
of content had by *E*. Note that while the state view is
incompatible with experiential conceptualism (assuming that the
concepts required by the latter are those used in a canonical
specification), it is neutral on the same-content thesis. Consider a
subject who doesn't possess the concept RED29 (where red29 is a
specific shade of red), but whose experience represents something as
being red29. Nothing in the state view prevents some other subject
from believing the contents of the first subject's experience.
Some philosophers (e.g., Crane 1992) have defended the state view
using arguments from richness and fine-grainedness of experience
(reviewed in
 Section 6.1).
 Other defenses of the state view include Stalnaker (1998a).



Another kind of content that is called 'non-conceptual
content' is Cussins' *construction-theoretic
content*; this is introduced in
 Section 4.2.


## 7. Content and Phenomenology



As the term 'experiences' is used here, it is definitional
of experiences that they have a phenomenal character. If they have
contents as well, then a question arises as to how these two features
are related. It is useful to contrast different views on the relation
between the content of an experience and its phenomenology by
considering *phenomenally indistinguishable experiences*, or
experiences with the 'same phenomenology', on the one
hand; and experiences with the *same content*, on the other. A
preliminary remark about this notion is in order.



The notion of phenomenal indistinguishability of unrepeatable
experiences cannot be defined as a statistical notion. Exactly how it
should be defined is a matter of controversy. Gottlob Frege and Moritz
Schlick raised doubts about the coherence of the notion of
*interpersonal* phenomenal indistinguishability, (these
'Frege-Schlick' doubts are discussed by Stalnaker 2000,
Shoemaker 1981 and 1996) In addition, though phenomenal
*indistinguishability* is commonly taken to be a sort of
phenomenal *sameness*, some philosophers use the expression to
pick out a merely epistemic notion, involving experiences that
subjects cannot distinguish (for discussion, see T. Williamson (1990),
Martin (2004), Siegel (2004), and entry on
 the disjunctive theory of perception.)
 Martin and Williamson regard it as a substantive claim that
experiences said to be 'phenomenally the same' have
anything more than an epistemic property of indistinguishability in
common.



There are several relations in which the content of an experience has
been thought to stand to its phenomenology. One position holds that
content suffices for phenomenology. A stronger position holds that the
content of experience is identical with its phenomenology. A third
position is that the phenomenology of an experience determines its
content. These positions and others are discussed below.


### 7.1 Representationalism about Phenomenology



*Representationalism* (or *intentionalism*) is the
thesis that phenomenal properties are determined by representational
properties. The thesis is sometimes stated as the supervenience claim
that phenomenal properties supervene on the representational
properties of an experience, so that any two experiences that have the
same representational properties have the same phenomenology.



Representationalism comes in many versions. One way in which versions
differ is that they may be claims about all sensory experience, or
just some kinds of sensory experience. (Tye 1995 defends a version of
representationalism about all sensory experience; most discussions to
date have focused on visual experience, as does Pautz 2010.)



A challenge to across-the-board representationalism comes from
experiences in modalities where it is unclear whether the experiences
represent happenings in the space outside the body, such as gustation,
olfaction, and experiences of afterimages. However, the notion of
accuracy conditions that defines the notion of content we've
been working with leaves it open whether those conditions pertain to
the world outside the mind or not. Consider whether olfactory
experiences represent anything about the smells or sources of smells
outside the body (for discussion see Smith (2002), chapter 5, Batty
2010, 2011, Richardson 2013). There is a coherent view on which an
olfactory experience can have accuracy conditions, even if they are of
the form 'an odor like so is present to me'. To take
another example, consider afterimages. According to Loar (2003),
experiences of afterimages represent 'luminous happenings in
strange spaces', which suggests that an experience of an
afterimage could include a content roughly like 'there is a
reddish luminous occurrence over there', where
'there' indicates a position in the 'strange
space'. (Perhaps the experience is neutral about whether the
space is inside or outside the mind). The notion of accuracy
conditions also leaves it open whether there could be accuracy
conditions that were met whenever a subject had an experience with
those conditions. For instance, suppose that sense can be made of the
notion of 'mental space' or 'subjective
space', and that some experiences have accuracy conditions
concerning smells, tastes or afterimages that reside in such space.
Given these suppositions, one might think that whenever an experience
represents that something occurs in such spaces, the experience is
accurate. In opposition to this idea, Bengson (2013) argues that the
visual experiences of pink glow or seeing blackness, and the auditory
experience of ringing in the ears fail to attribute color, luminance,
or auditory properties to anything at all, and so resist analysis in
terms of accuracy conditions. 



Another potential problem for across-the-board representationalism
concerns experiences in different sense-modalities. As stated,
representationalism requires that any two experiences with the same
content have the same phenomenology, even if the experiences occur in
different sensory modalities. Seeing something square and touching
something square are phenomenally different. If representationalism is
true for both haptic-tactile and visual experiences, then these
experiences cannot have the same content. Normally two such
experiences would probably not have exactly the same content anyway,
for instance if the visual experience represented properties (e.g.,
colors) that the tactile experience didn't. But abstracting away
from those differences, there is a strong intuition that the visual
phenomenology correlated with visually representing squareness differs
from the tactile phenomenology correlated with feeling something to be
square. It seems that across-the-board representationalism must either
(i) deny the intuition that the visual phenomenology correlated with
visually representing squareness differs from the tactile
phenomenology correlated with feeling something to be square, or else
(ii) deny that the contents related to representations of squareness
really are the same after all, so that each modality (or natural
grouping of modalities) has a special kind of content to call its own,
and one cannot experience by one modality exactly the same thing as
one can experience by another. Response (ii) is illustrated by one
answer to Molyneux's question (see entry on
 Molyneux's problem)
 whether someone born blind and was familiar with the feel of a cube
could recognize a cube upon seeing it for the time, without also
touching it. If the answer to Molyneux's question is that the
previously blind person could not visually recognize cubes, one might
conjecture that this is because the shape properties represented by
visual experience on the one hand and by haptic tactile experience on
the other differ.



Another response to this potential problem revises the thesis of
representationalism, construing the representational properties that
determine phenomenology as attitude-content complexes rather than
contents alone. For example, Chalmers 2004 distinguishes *pure
representational properties*--the property of having a
certain content--from *impure representational
properties*--the property of having a certain content
represented in a certain way. Examples of impure representational
properties include the property of having a certain content
represented in modality *M*, and that of having attitude
*A* to a certain content. *Impure representationalism*
is then the thesis that impure representational properties determine
phenomenology, so that any two experiences with the same impure
representational properties have the same phenomenology. This position
allows that experiences in different modalities, or experiences that
instantiate different attitudes, could have the same content, yet
differ phenomenally because, say, one is visual and the other
kinesthetic. For instance, perhaps both represent that one's
hand is moving, or that something is round. Versions of impure
representationalism are held by Lycan 1996, Chalmers 2004, 2006, Pautz
2010.


### 7.2 Does Phenomenology Determine Content?



The converse of representationalism is the thesis (put roughly) that
the phenomenology of an experience determines its content. The thesis
is often more precisely formulated as a supervenience claim. Two
theses here should be distinguished:



> 
> (1) For any two phenomenally identical experiences, there are some
> accuracy conditions that they share.
> 
> 
> (2) Any two phenomenally identical experiences have the same accuracy
> conditions.
> 
> 
> 



Claim (2) says that all accuracy conditions are determined by
phenomenology, claim (1) says that at least some are.



Claim (1) constrains which contents experiences have. Shoemaker
develops this idea in a series of papers (1994, 2005). See also
Chalmers (2004, 2005).



The two theses above are both entailed by a strong version of
representationalism, which combines representationalism with the
thesis that any two experiences with the same phenomenal properties
have the same representational properties. This sort of
representationalism is sometimes held in the guise of an identity
claim: the claim that phenomenal properties are identical to
representational properties. Versions of this view are defended by
Dretske 1995, Tye 2000, and Carruthers 2000. But theses (1) and (2)
can be held even if one rejects these strong representationalist
theses. Some philosophers hold (1) on the grounds that the
representational content of an experience is grounded in its
phenomenology. According to Horgan and Tienson 2002, for example,
there is a kind of content that experiences have in virtue of their
phenomenology, so that their phenomenology has explanatory priority
over the content itself. This view is suggested by Siewert (1998) and
defended by Kriegel (2002; 2013), and see entry on
 phenomenal intentionality.




Some philosophers deny both (1) and (2) on the grounds that the
accuracy-conditions of an experience are determined in part by
extra-cranial features, while the phenomenology of an experience is
not. These philosophers are internalist about phenomenology, but
externalist about experience content. (Block 1990 and 1996, Speaks
2009).


## 8. Theories of Intentionality for Experience



So far, we've discussed some reasons to think that there are
contentful experiences, and some questions about what sorts of
contents there might be. A different cluster of questions concerns
what makes it the case that an experience has the contents it does.
How is representation of any property is possible? Two sorts of
theories addressing this question are addressed in
 Section 8.2
 and
 Section 8.3,
 and some possible constraints on such theories are reviewed in
 Section 8.1.


### 8.1 Externalism vs. Internalism About Perceptual Content



*Externalism about experience content* (or
*experience-content externalism*) is the thesis that subjects
alike in properties that are intrinsic to them need not share the same
experience contents. If experience-content externalism is true, then
what makes it the case that an experience has the content it does
depends on external relations to things outside the subject's
skin, such as social relations between the subject and others, or
causal relations to things in the environment. Defenders of
experience-content externalism include Dretske, Lycan, and Tye, all of
whom argue for experiential externalism on the grounds that the
alleged best naturalistic theories of intentionality for experience
are externalist theories. (For discussion of externalism about the
content of other mental states, see the entry on
 external theories of content.)



A thesis opposed to experience-content externalism is
experience-content *internalism*. Put roughly, this is the
thesis that experience content is determined entirely by the
individual's intrinsic properties. *Total experience-content
internalism* is the thesis that *all* experience content is
determined by the individual's intrinsic properties (i.e., that
two subjects alike in all intrinsic respects will have exactly the
same experiential contents). *Partial experience-content
internalism* is the thesis that there is a *sort* of
experiential content that is determined by a subject's intrinsic
properties (i.e., two subjects alike in all intrinsic respects will
have the same experiential contents of this sort. This thesis allows
that experiences may also have some externally determined contents.
Total experiential internalism is defended by Segal 1991 and Matthews
1985; partial experience-content internalism is defended by Chalmers
2004.



Externalism and internalism about contents are distinct theses from
externalism and internalism about phenomenology. *Internalism about
phenomenology* is the thesis that intrinsic duplicates are
phenomenal duplicates. *Externalism about phenomenology* is the
denial of this thesis, on the grounds that phenomenology is determined
in part by factors outside a subject's skin. Externalism about
phenomenology is sometimes motivated by representationalism about
phenomenology combined with externalism about content. If one is
externalist about experiential content, and if one holds that the
content and the phenomenology of an experience co-vary, then one must
also be an externalist about phenomenology. This thesis is defended by
Dretske (1995) and Lycan (2001), and criticized by Block (1990) and
(1996). For further discussion, see the entry on
 external theories of content.



One of the main motivations for experience-content internalism is the
idea that only internally individuated states can figure in
psychological explanations. This mirrors one of the main motivations
for internalism about the contents of other mental states. The general
issue is reviewed in the entry on
 externalism.
 In the case of experience, philosophers have pursued this debate with
respect to Marr's computational theory of vision, one of the
leading empirical theories of visual processing. The debate is over
whether Marr's theory itself posits any externally-individuated
contents, or whether the contents it posits are all individuated
internalistically. If Marr's theory is correct and explanatory,
and if the representational contents it posits are externally
individuated, then it provides a counter-example to
individualists' claims that only internally-determined contents
figure in psychological explanation. The debate thus focuses on
exactly what commitments Marr's theory makes about the
individuation of perceptual content.



Though Marr's theory posits representational states, it does not
make use of the notion of a visual experience, and it is an open
question how experiences map onto the stages of computational visual
processing posited by the theory (see Marr (1982), section 7.2 for
Marr's own brief discussion of this issue). Marr's theory
seeks to explain how the visual system arrives at representations of a
three-dimensional array given retinal stimulation as input. The
retinal stimulations, or 'gray arrays', are computational
descriptions that represent light and intensity values in a
two-dimensional coordinate system. According to Marr, the visual
system computes a description of a three-dimensional scene in three
stages. First, given the gray arrays, it computes a 'primal
sketch' of reflectance changes on the surface outside the
viewer. Next, with the primal sketch as input, it computes a
'2.5-D sketch' of this surface, a sketch that explicitly
represents information concerning depth and contours of the surfaces
relative to the viewer. (The depth information concerns only facing
surfaces, so that the 2.5 sketch contains no information--and
therefore no misinformation--about how surfaces continue out of
view.) Finally, given the 2.5 sketch as input, the visual system
computes information concerning all three dimensions of objects, one
that describes their shapes and orientations. According to the theory,
the computation at each stage combines the input from the previous
stage with assumptions that are supposedly built into the visual
system.



The debate is over whether Marr's theory allows two subjects,
call them *V* and *V*\*, to have different visual
contents, when *V* is a normal perceiver on earth, and
*V*\* is an intrinsic duplicate of *V*, with the same
gray arrays as those had by *V*, and undergoes the same
sequence of computations, viewed internally. *V*\*'s gray
arrays, however, have different distal causes. Borrowing an example
from Burge (1986), suppose that *V*'s gray arrays are
typically caused by shadows, and occasionally caused by cracks;
whereas *V*\* lives in a world where the optical laws are
different, and there are no instances of the sort of shadows that
cause *V*'s gray arrays. According to Burge, Marr's
theory says that the contentful visual states that are computed from
*V*'s gray arrays always represent shadows, and thus the
ones that arise from gray arrays caused by cracks are misperceptions;
while the contentful visual states that are computed from
*V*\*'s gray arrays represent cracks. Neither *V*
nor *V*\* can discriminate the relevant sorts of cracks from the
relevant sort of shadows, but according to Burge this is not
sufficient to make their contents the same. According to Gabriel
Segal, in contrast, the contentful visual states computed from both
*V* and *V*\*'s gray arrays represent a property
more general than the property of being a crack or the property of
being a shadow--a 'crackdow'. (For further
discussion, see Matthews 1988, Burge 1988, Davies 1991, Shapiro 1993,
Egan 1991, and Patterson 1996.)


### 8.2 Functionalist Informational Theories of Experience



Dretske and Tye have each proposed that an experience has the contents
it does in virtue of having certain functional properties.



According to Dretske, an experience has its content fixed by the
biological, phylogenetically determined function of the system (or
combination of systems: (1995), 22) of which it is a state. The
function of the system is to provide information: for instance, the
function of the auditory system is to provide information about pitch,
intensity, timbre, and direction of sound, and it does this by
occupying different states corresponding to different values for each
of these properties. The different states are all the different
auditory experiences that a given system is capable of being in. The
same main idea is developed by Ruth Millikan, who focuses on mental
content generally rather than on experience content *per
se*.



Tye's account of experience content derives from the theories of
intentionality for belief developed by Stampe (1977) and Stalnaker
(1984). According to Tye, an experience *S* of creature
*c* has the content that *p* just in case: "If
optimal conditions were to obtain, *S* would be tokened in
creature *c* if and only if *P* were the case; moreover,
in these circumstances, *S* would be tokened in *c*
because *P* is the case" (2000, 136, note omitted; cf.
1995, 101). For the case of visual experiences, Tye, like Dretske,
appeals to the design of the visual system to explain what
"optimal conditions" are: "In the case of evolved
creatures, it is natural to hold that such conditions for vision
involve the various components of the visual system operating as they
were designed to do in the sort of external environment in which they
were designed to operate" (Tye 2000, 138).



Both kinds of theories are *externalist*: according to them,
what makes it the case that a subject's mental state has the
content it does is in part facts about the subject's
environment. Any objections to externalism about mental content are
thus also objections to these theories of intentionality. For
instance, suppose there was a creature, Swampman, who suddenly popped
into existence due to random conglomeration of particles, and happened
to be an intrinsic molecular duplicate of, say, Jerry Fodor. Pure
externalist theories (that is, theories that hold that the only way
mental states can have content is by standing in the right external
relations to the subject's environment) are committed to denying
that Swampman would have any contentful mental states. Some
philosophers have found this commitment counterintuitive. For further
discussion of this objection and others, see the entry on
 external theories of mental content.



A central challenge facing Dretske's and Millikan's theory
is to specify the relevant notions of *informational* system
and *function* in an informational system. One question in the
area is whether informational systems and functions within them are
contained within an organism, or whether they rather encompass
multiple organisms in a community. Much work by Millikan has been
devoted to this topic. According to her, an informational system
encompasses both creatures who produce representations, and creatures
who use or receive them; and the relevant notion of function is
supposed to be defined in terms of both parts of such a system. For
instance, in a bee dance, what makes it the case that the bee dance
represents the location of nectar is in part that other bees respond
to it by flying to the nectar. A analogous challenge for co-variation
theories inspired by Stampe and Stalnaker is to specify what the
relevant 'becausal' relations are. Until these central
notions are pinned down, the theories remain programmatic.



One objection that has been raised against both kinds of informational
theories of experience (those that invoke biological functions, and
those that invoke co-variation) is that these theories are
insufficiently general. According to the objection, there can be
properties represented in a subject's experience even if she has
not been in causal contact with instances of those properties before,
and which it is no part of the biological function of the visual
system to represent. For example, consider impossible scenes depicted
in Escher drawings, or a hallucination of a color that one has never
seen before (such as Hume's missing shade of blue). Suppose
experiences can represent that one is standing before an Escher
staircase, or that something is the missing shade of blue. According
to Tye's theory, this can happen only if in optimal conditions
that type of experience is tokened because these things are the case.
But since it is logically impossible to be standing before an Escher
staircase, this condition can never be met. And if it is nomologically
impossible to be seeing anything that is the missing shade of blue,
then even if the proposed necessary condition in principle can be met,
the worlds in which it is met would seem to be irrelevant ones for the
purpose of the theory. So, the objection concludes, Tye's theory
must predict that Escher staircases and missing shades of color cannot
be represented in experience. For further discussion of objections to
informational theories, see the entry on
 causal theories of mental content.
 


### 8.3 Phenomenal Intentionality



According to some philosophers (e.g., Horgan and Tienson 2002; Kriegel
2002, 2013; Siewert 1998), there is a some content of experience that
is constitutively determined by the experience's phenomenology
alone (Horgan and Tienson 2002, p. 524). Horgan and Tienson call this
thesis *phenomenal intentionality* (See entry on
 phenomenal intentionality).
 A consequence of the thesis is that phenomenology enjoys explanatory
priority over intentionality. Proponents of phenomenal intentionality
take phenomenology as a primitive notion, which cannot be reduced to
content, and then try to explain (at least some kinds of) content in
terms of it.



If the phenomenal intentionality thesis is true, then phenomenology
cannot be reduced or identified with content, or with the having of
content. The thesis thus stands in contrast to views defended by
Dretske and Tye according to which the content of experience is wholly
explained in causal or functional terms, where one does not need to
invoke phenomenology to explain why an experience has the content it
has. These latter views leave open the possibility that the content of
an experience enjoys explanatory priority over its phenomenology, so
that one can explain phenomenology in terms of content.



Together with the assumption (made by Horgan and Tienson and by
Kriegel) that phenomenology is narrow (i.e., shared by intrinsic
duplicates), the thesis of phenomenal intentionality yields an
*internalist* theory of experience content. This introduces
another respect in which phenomenal intentionality stands opposed to
some versions of functionalist informational theories of experience
content--namely, those versions that hold that the *only*
contents experiences can have are those had in virtue of the
functional properties of the sort discussed in
 Section 8.2.
 If the thesis of phenomenal intentionality is true and phenomenology
is narrow, then there are narrow contents that are constitutively
determined by phenomenology. Any objections to narrow content will
thus also apply to this thesis. For further discussion of narrow
content, see the entry on
 narrow content.


## 9. Directions for Future Research



There is much more research in philosophy to be done on the contents
of experience. A great deal of theorizing has focused on visual
experiences. Even so, none of the questions discussed above are fully
settled, and so there is plenty of opportunity for further research on
any of those topics. Additional topics ripe for future research
include questions such as: what is the relation between perceptual
content and perceptual contact with reality?; how do experiences in
different modalities interact?; what role does experiential content
play in reasoning, in intentional action and more generally in being
an agent?; and how are perceptual constancies reflected in the
contents of experience?; what notion of contents of experience is most
theoretically useful for unconscious perception, and how may the
latter be distinguished among the varieties of subpersonal information
processing?