## 1. The Ancient Background and the Formation of the Concept



The English words 'representation' and 'to
represent' derive via Old French from the Latin words
'repraesentatio' and 'repraesentare,' but
these are by no means commonly used words in classical Latin. In late
ancient thought it is foremost Quintilian and Tertullian that uses the
terms in a philosophically interesting way. It was not until the
twelfth century Latin translation of Avicenna's *De
anima* that these terms became frequently used in connection with
cognition and the mind or the intellective soul (see Lagerlund
2007b).



The Latin translators of Avicenna rendered several related terms in
Arabic all related to cognition and the internal senses with the Latin
'repraesentatio'. In doing so they, intentionally or not,
formed the concept of representations in the soul. Representation in
the Latin translation of Avicenna is associated with all five
faculties. Forms received through the common sense and stored in the
phantasia are called representations. The imaginative or cogitative
faculty combines and divides representations collected in the
phantasia to make new representations, which might not have any real
object corresponding to them. The senses apprehend the sensible forms
of the objects perceived and the estimative faculty apprehends the
'intentio' or 'ma'na' of the perceived
object. Representations in the imagination are also the basis for
intellectual activity, according to this view of cognition:



> 
> In the intellect, the form of animal is of the sort that agrees with
> one and the same definition of many particular [things]. Thus, one
> form in the intellect will be related to many things, and it is in
> this respect that it is universal, because it is one intention in the
> intellect ... which is evident since, of those [things]
> represented by the form in the imagination, the intellect has
> plundered the intention of its accidents [and] acquired the form in
> the intellect. (*Liber de philosophia prima sive scientia
> divina* V, cap. 1, p. 237)
> 



Avicenna here describes the process of abstraction, or how the
representation in the imagination of particular things becomes
universal in the intellect. The universal forms are abstracted from
representations in the imagination and flow from the active intellect
into the passive. Note, however, that the terminology of
representation is never used in relation to the intellect. It is
always the internal senses that represent in Avicenna and not the
intellect or the external senses (see Lagerlund 2007b, for a table of
the whole range of terms translated by 'representation' in
Avicenna's works.)



One of the reasons 'representation' is only used for the
internal senses is that representations are thought of as images. The
notion of linguistic representations or representations as signs is
not present in Avicenna's work or any other work of the time. It
seems instead to derive from logic. Early logic works like Garlandus
Compotista's *Dialectica* (17) and Abelard's
*Dialectica* (II, 188) discussed a distinction between a
word's signification by imposition and representation. A
denominative term such as 'white' signifies by imposition
a substance that is white, but it signifies by representation the
whiteness inhering in the substance. The white thing stands in for or
is an instantiation of whiteness; white is re-presented in the object.
Garlandus mentions the example of a traveler
('*viator*') who can be said to represent a road
('*via*'). The term 'traveler'
signifies by imposition the human being who is a traveler, but also
represents the road the traveler travels on. It is exactly this usage
of representation applied to mental signs that becomes important with
Ockham and Buridan.


## 2. Thomas Aquinas and Formal Sameness



The most influential theory of thought in the thirteenth century goes
back to Aristotle and has its foremost medieval defender in Thomas
Aquinas. It rests on viewing mental representations or intelligible
species, as Aquinas calls them, as sameness of form. The explanation
for why thoughts are about something, exhibit intentionality, or
represent is that the form of the object thought about is in the mind
of the thinker. According to a popular metaphor, thinking something,
on this view, is being the object thought about in the sense that the
intellect becomes the object or takes on its form.



Following Aristotle in *De anima* III.4, Aquinas argues, that
the mind or the intellective part of the soul has no nature or rather
it is nothing before it thinks of something. The active intellect
abstracts the intelligible species from the sensitive species in the
internal senses and places it in the potential intellect. Aquinas is
here very close to the view we saw Avicenna defend above. The species
actualizes the potential intellect as a form actualizes a potency. The
intelligible species in the potential intellect constitutes the
thought. The intellect is immaterial, according to Aquinas, and since
he also famously thinks that matter is the principle of individuation,
the intelligible species in the potential intellect is not individual,
but universal. This is why Aquinas holds that a thought is always
universal. 



There are many problems associated with this view of mental
representation. A famous problem is: why are the daffodils outside my
soul not about my thought of the daffodils? The forms inside and
outside my mind are the same, suggesting that mental representation is
symmetrical. Aquinas has a famous answer to this problem, which is
that the daffodils in the garden are not about my thought because of
the mode of the form's presence in them. The forms in the
daffodils are really or naturally present whereas in my mind the
universal form is spiritually or intentionally present.



The distinction between forms being really/naturally or
spiritually/intentionally present is central to Aquinas's theory
of cognition. A form may be present somewhere without literally making
whatever substance it informs into something else. Colors in the air,
for example, do not make the air really colored: we see colors in the
objects around us but not in the intervening air, although they must
be there spiritually if sensation is to be a causal process. This
means, of course, that the air must somehow contain the color, which
entails that intentionality is not a mark of the mental for Aquinas.
The air is not in itself a mind (for discussion, see Pasnau 1997,
Chap. 2, and for a completely different take see Brower and
Brower-Toland 2008).


## 3. Peter Olivi and the Rejection of Formal Sameness



One of the first to criticize the species theory of cognition, in the
late thirteenth century, was Peter Olivi. He argued, contrary to
Aristotle and Aquinas, that the mind is active in its cognition of the
world; it attends to the object, and it is this move on his part that
puts the species theory of cognition in a completely different light.
In fact, there seems little point in postulating a species through
which the object is cognized. He argues:



> 
> Third, because the attention will tend toward the species either in
> such a way that it would not pass beyond so as to attend to the
> object, or in such a way that it would pass beyond. If in the first
> way, then the thing will not be seen in itself but only its image will
> be seen as if it were the thing itself. That is the role of a memory
> species, not a visual one. If in the second way, then after the
> inspection of the species it will inspect the object in itself. In
> this way it will cognize the object in two ways, first through the
> species and second in itself. It will indeed be like when someone sees
> an intervening space and then beyond that sees the fixed object.
> (Peter John Olivi, *Quaestiones in secundum librum
> Sententiarum*, III, q. 74, 123.)
> 



In this passage, it seems clear that for Olivi the species is a thing
in itself and that there really are three things involved in the
cognition of an object: the object, the species, and the cognizer. The
species is on his view a representation, namely a thing that stands in
for the object in the mind. The main problem he sees with the theory
is hence epistemological. How can we be sure we are cognizing the
object and not the species (see Toivanen 2009, Chap. 4 and Adriaenssen
2011). Olivi hence argues that this third representing thing is not
needed and that the mind can attend to the object directly. Ockham is
later on in the early fourteenth century to repeat a similar argument
against the species theory.



Both Olivi and Ockham seem to take it for granted that species are
representations and hence a thing added to the object and the
cognizer. There were, however, two versions of the species theory of
cognition in the thirteenth century. The most influential one was
foremost associated with Roger Bacon. According to him, species are
representations, that is, real extended images like objects
representing the thing cognized to the cognizer. The other version of
the theory was defended by Aquinas. According to him, species were not
representations but the forms themselves of the objects cognized under
a different mode of being. The species were not real but spiritual and
as such there are no physical change of for example the eye in a
visual perception; only a spiritual one.



Olivi's objection mentioned above does not apply to
Aquinas' theory since species are not real representations on
that view. Olivi himself seems aware of this, however, and says that
if the species has spiritual being, then they cannot: "truly and
naturally flow from a natural, corporeal form, [and] not really and
truly inform a natural body, e.g. the air or the eye."
(*Sententiarum* II, q. 73, 87.) On Aquinas' theory the
species cannot affect the sense organ and cause a cognition, he seems
to think. The species cannot hence fulfill the role they are supposed
to play in a theory of cognition or a theory of vision.



Olivi does not straight our reject all species, however, since he
thinks memory utilizes species. These species are representations and
they are constructed by us. He explains it in the following
passage:



> 
> Cognitive acts are effected by the [cognitive] power -- not,
> however, through its nude essence. Rather, in all [cognitive acts] an
> actual attention, actually terminated upon the object, is
> required.... And therefore, when the exterior thing
> in-and-of-itself (per se) is not placed before the attention, there
> must be a memorative species placed before it in lieu of the object,
> which [the species] is not the origin of the cognitive act, except
> insofar as it serves as a term for or representative of the object.
> (*Sententiarum* II, q. 74, 113.)
> 



This is the most common usage of species after Olivi, that is, that
species are representative (see Adriaenssen 2017).


## 4. Henry of Ghent and John Duns Scotus on Mental Content



For various reasons, the late thirteenth century saw an increased
interest in epistemology. One reason for this was the development of
new theories of mental representations and intentionality. Some of
these developments were due to problematic features of, on the one
hand, Aquinas's view of mental representation and on the other,
of Henry of Ghent's interpretation of Augustine's view of
divine cognition. Aquinas seems to have held that the intelligible
species is supposed to play a dual role both as a universal common to
all of us thinking it and as my individual thought. It is hard to see
how such a view can be maintained without the introduction of some
kind of distinction. Henry on the other hand reinterprets
Augustine's doctrine of divine ideas and introduces a
distinction between the ideas and the divine nature. The ideas are
possibilia or the natures of possible things to be created (de Rijk
2005: 81-84).



Both of these views contribute to the introduction of a distinction
between the vehicle and the content of a representation. The
distinction developed by Henry in relation to the divine nature was
almost immediately taken up into the debates about human cognition. It
was applied to Aquinas's theory of mental representation, taking
it a step further by introducing a distinction between the thing
representing and the thing represented. 



John Duns Scotus was instrumental in adapting this view to human
cognition. Scotus's implemented Henry's distinction and
treated the thing that does the representing as a mental act or
concept, which ontologically speaking is an accident of the mind, and
the thing represented as the form of the object thought about. Scotus
claimed that the accident or mental act is subjectively in the soul,
whereas the object being represented is present objectively, or has
objective being in the mind. He also said that the object exists as
represented to express the content side of the mental representation
(Ord. I, d. 3, pars 3, q. 1, n. 382) Scouts can through this
distinction also maintain that all spiritual change supervenes on a
real change (see Cross 2014). 



Scotus thus had a clear way of expressing what Brentano later called
intentionality, that is, the way the object of thought exists in the
mind. It has objective existence in the mind on his view, which later
came to be regarded as the mark of the mental (see Normore 1986;
Pasnau 2003; King 2007; Cross 2014). Although the advantages of this
approach over Aquinas's are clear, problems remains concerning
the ontological status of these mental contents. The medieval debate
here is famous and features a wide variety of opinions (for a survey,
see Tachau 1988). Scotus himself says that thought objects have a
diminished kind of being, which is supposed to be a state between real
being and no being at all. Although first accepting a similar view,
Ockham would later subject this view to much criticism.


## 6. William Ockham and Mental Language



The theory of mental language in the fourteenth century was foremost
developed by William Ockham. It rests on a theory of mental
representation that combined the notions of cause and signification. A
concept or a mental term on this view represents because it is caused
efficiently by a thing in the world. It signifies that thing also
because of the causal relation between them. On Ockham's view, a
mental representation or concept is caused by an intuitive cognition.
He explains:



> 
> Intuitive cognition is the proper cognition of a singular not because
> of its greater likeness to one thing more than another but because it
> is naturally caused by one thing and not by another; nor can it be
> caused by another. If you object that it can be caused by God alone, I
> reply that this is true: such a visual apprehension is always apt to
> be caused by one created object and not by another; and if it is
> caused naturally, it is caused by one thing and not by another, and it
> is not able to be caused by another. (*Quodlibeta Septem* 1.13)
> 



According to Ockham's metaphysics there are only individuals in
the world so that when an individual causes a concept to exist in the
mind, it causes an individual concept and hence a singular conception
of itself. Nothing else can cause that concept (except perhaps God).
The singular concept functions as the word of the object that caused
it in our language of thought. It is an atomic constituent that can
then be combined to form more complex concepts or sentences in the
language.



Ockham's notion of concept acquisition and mental representation
is developed as part of a very sophisticated theory of thought
involving not only a theory of signification, but also a whole range
of logico-semantic properties such as connotation and supposition. It
explains how concepts, which in turn are the direct objects of belief
and knowledge, are assembled into mental sentences describing the
world (for the details, see Panaccio 2004).


## 5. John Buridan and Vague Concepts



Ockham and John Buridan's accounts of thought are on the one
hand very similar, but on the other hand there are fundamental
differences between them. This is particularly true about their view
of mental representation. A case in point is their views of singular
thought. They both start out from the same idea, that is, that
thinking something singular is having a singular concept in mind, but
they disagree fundamentally on what a singular concept looks like and,
foremost, on how it manages to latch onto the world. On Ockham's
account a concept is singular because its cause is proper, as he calls
it, and proper causes are necessarily tied to one object. But on
Buridan's account, a singular concept is singular because of its
semantic complexity (see Klima 2001: xxxviii-xlii and 2009:
40-56). It has a descriptive content that enables it to narrow
down its signification. However, Buridan retains Ockham's view for
some terms (for the significance of this difference from Ockham, see
Klima 2009: 69-89).



Buridan thinks that we always in the first instance cognize or
conceive of something as singular. There are, however, two kinds of
singular concepts, namely, vague and determinate singular concepts.
There are also two ways a singular concept or mental term can be
acquired. The vague terms are acquired through perception and involves
a direct acquaintance with the perceived object. Buridan describes how
we see something approaching from a distance and cognize it as
'this thing', then as 'this body', then as
'this animal', then as 'this donkey', and
finally as 'Brunellus.' (For more on this and its
significance see Normore 2007, Black 2011, Lagerlund 2006, and
Lagerlund 2014.) These demonstratives describe circumstances in which
we cognize something singularly, and they come together under a
description of a singular thing, which we impose on it ourselves or
have learned the name of, in this case, 'Brunellus.' The
vague singular term is a name for a circumstance in which we cognize a
non-determinate singular thing as something, for example, an
individual thing, body, donkey, etc. There is, however, another way a
singular can be formed and that is by imposing or associating it with
a name of some descriptions or properties that we never have had a
corresponding vague singular cognition of, since we have no actual
acquaintance with the thing through sense perception. These are
singular terms like 'Socrates' or 'Plato.'
They have never directly existed before our senses and intellect. We
only know them through descriptions. Buridan explains the difference
in *Summulae de Dialectica* 8.2.1 (Buridan *SD*, 633): 



> 
> Another reason is that things cannot be cognized as singular unless
> they are cognized as something in the prospect of the cognizer.
> Therefore, if I did not perceive Socrates, you cannot tell me what I
> should understand by 'Socrates,' except by using common
> terms, the aggregate of which can just as well apply to something else
> as to Socrates. So, should another thing be created similar to
> Socrates in all of its external features [circumstantiis], this
> [aggregate] would no longer be the definition of
> 'Socrates', for it would not be proper to it, nor
> convertible with it.
> 



As explained above, only terms that derive from actual sense
cognitions (what he here calls cognition in 'the prospect') are
properly singular. They have an element that fixes them to the thing
cognized.



He seems to think that all proper singular terms are collections of
descriptions of a thing under a name. This goes for singulars that I
am acquainted with as well as singulars I have no sense acquaintance
with. Assume that I have the concept 'Brunellus' in my
mental language, which I have formed through vague singulars, that is,
through circumstances in which I have perceived him as this or that.
These vague singulars express the demonstrative aspect of my
experience of Brunellus. They come together under the singular term
'Brunellus' with all the things I 'know' about
him. I have no such demonstrative element in my singular terms of
'Socrates' and 'Plato,' since they have never
and cannot exist in a direct sense cognition. In that respect, there
is nothing part of such singular terms that discriminate them from
other term than the sum of descriptions I have sorted under these
terms. They will, to use Saul Kripke's terminology, never
rigidly pick out what they signify. 'Brunellus' on the
other hand will, because of the demonstrative element derived from my
actual interactions with him. (For a slightly different take on this preserving the rigid designation of terms like 'Socrates' or 'Plato' see Klima 2009, Chapter 4, Section 4.2.)



Buridan is defending an internalist semantics for singular terms. It
is not internalist because of the two different kinds of singular
terms or that they both are collections of descriptions and
circumstances in which we have interacted with something, but instead
because the imposition of these terms describes a process that is
completely internal to the agent. It is up to us to sort names with
descriptions and circumstances and, hence, impose certain names on
these descriptions and circumstances. Give this, two speakers of the
same language could have the same name for an individual and even be
using it for the same individual despite the fact that the names they
use have different content or meaning because they have different
descriptions in mind during the conversation. Meaning is, hence, in
the head for Buridan. A position quite different from Ockham (for more
on this see Panaccio 2017 and Lagerlund 2024).