## 1. A Sketch of Kant's View of the Mind




In this article, we will focus on Immanuel Kant's (1724-1804) work
on the mind and consciousness of self and related issues.





Some commentators believe that Kant's views on the mind are
dependent on his idealism (he called it transcendental idealism). For
the most part, that is not so. At worst, most of what he said about the
mind and consciousness can be detached from his idealism. Though often
viewed as a quintessentially German philosopher, Kant is said to have
been one-quarter Scottish. Some philosophers (often Scottish) hold that
'Kant' is a Germanization of the Scottish name
'Candt', though many scholars now reject the idea. It is
noteworthy, however, that his work on epistemology, which led him to
his ideas about the mind, was a response to
 Hume
 as much as to any other philosopher.




In general structure, Kant's model of the mind was the dominant
model in the empirical psychology that flowed from his work and then
again, after a hiatus during which behaviourism reigned supreme
(roughly 1910 to 1965), toward the end of the 20th century,
especially in cognitive science. Central elements of the models of the
mind of thinkers otherwise as different as Sigmund Freud and Jerry
Fodor are broadly Kantian, for example.




Three ideas define the basic shape ('cognitive
architecture') of Kant's model and one its dominant method. They
have all become part of the foundation of cognitive science.


1. The mind is a complex set of abilities (functions). (As Meerbote 1989
and many others have observed, Kant held a functionalist view of the
mind almost 200 years before functionalism was officially articulated
in the 1960s by Hilary Putnam and others.)
2. The functions crucial for mental, knowledge-generating activity are
spatio-temporal processing of, and application of concepts to, sensory
inputs. Cognition requires concepts as well as percepts.
3. These functions are forms of what Kant called synthesis. Synthesis
(and the unity in consciousness required for synthesis) are central to
cognition.


 These three ideas are fundamental to most thinking about cognition now.
Kant's most important method, the transcendental method, is also at the
heart of contemporary cognitive science.


* To study the mind, infer the conditions necessary for experience.
Arguments having this structure are called *transcendental
arguments*.




Translated into contemporary terms, the core of this method is
inference to the best explanation, the method of postulating
unobservable mental mechanisms in order to explain observed
behaviour.




To be sure, Kant thought that he could get more out of his
transcendental arguments than just 'best explanations'. He
thought that he could get *a priori* (experience independent)
knowledge out of them. Kant had a tripartite doctrine of the *a
priori.* He held that some features of the mind and its knowledge
had *a priori* origins, i.e., must be in the mind prior to
experience (because using them is necessary to have experience). That
mind and knowledge have these features are *a priori* truths,
i.e., necessary and universal
 (B3/4)[1].
 And we can come to know these
truths, or that they are *a priori* at any rate, only by using
*a priori* methods, i.e., we cannot learn these things from
experience (B3) (Brook 1993). Kant thought that transcendental
arguments were *a priori* or yielded the *a priori* in
all three ways. Nonetheless, at the heart of this method is inference
to the best explanation. When introspection fell out of favour about
100 years ago, the alternative approach adopted was exactly this
approach. Its nonempirical roots in Kant notwithstanding, it is now the
major method used by experimental cognitive scientists.




Other topics equally central to Kant's approach to the mind have hardly been discussed by cognitive science. These include, as we will see near the end, a kind of synthesis that for Kant was essential to minds like ours and what struck him as the most striking features of consciousness of self. Far from his model having been
superseded by cognitive science, some things central to the model have not even
been assimilated by it.


## 2. Kant's Critical Project and How the Mind Fits Into It




The major works so far as Kant's views on the mind are concerned are
the monumental *Critique of Pure Reason (CPR)* and his little,
late *Anthropology from a Pragmatic Point of View*, first
published in 1798 only six years before his death. Since the
*Anthropology* was worked up from notes for popular lectures, it
is often superficial compared to *CPR.* Kant's view of the mind
arose from his
 general philosophical project
 in *CPR* the following way. Kant aimed among other things
to,


* Justify our conviction that physics, like mathematics, is a body of
necessary and universal truth.
* Insulate religion, including belief in immortality, and free will
from the corrosive effects of this very same science.



 Kant accepted without reservation that "God, freedom and
immortality" (1781/7, Bxxx) exist but feared that, if science
were relevant to their existence at all, it would provide reasons to
doubt that they exist. As he saw it and very fortunately, science
cannot touch these questions. "I have found it necessary to deny
*knowledge*, ... in order to make room for
*faith."* (Bxxx, his italics).




Laying the foundation for pursuit of the first aim, which as he saw it
was no less than the aim of showing why physics is a science, was what
led Kant to his views about how the mind works. He approached the
grounding of physics by asking: What are the necessary conditions of
experience (A96)? Put simply, he held that for our experience, and
therefore our minds, to be as they are, the way that our experience is
tied together must reflect the way that, according to physics, says objects in
the world must be tied together. Seeing this connection also tells us
a lot about what our minds must be like.




In pursuit of the second aim, Kant criticized some arguments of his predecessors
 that entailed if sound that we can know more about the mind's consciousness of
itself than Kant could allow. Mounting these criticisms led him to some extraordinarily
penetrating ideas about our consciousness of ourselves.




In *CPR,* Kant discussed the mind only in connection with his
main projects, never in its own right, so his treatment is remarkably
scattered and sketchy. As he put it, "Enquiry ... [into] the
pure understanding itself, its possibility and the cognitive faculties
upon which it rests ... is of great importance for my chief
purpose, ... [but] does not form an essential part of it"
(Axvii). Indeed, Kant offers no sustained, focussed discussion of the
mind anywhere in his work except the popular *Anthropology,*
which, as we just said, is quite superficial.




In addition, the two chapters of *CPR* in which most of
Kant's remarks on the mind occur, the chapter on the Transcendental
Deduction (TD) and the chapter on what he called Paralogisms (faulty
arguments about the mind mounted by his predecessors) were the two
chapters that gave him the greatest difficulty. (They contain some of
the most impenetrable prose ever written.) Kant completely rewrote the
main body of both chapters for the second edition (though not the
introductions, interestingly).




In the two editions of *CPR,* there are seven main
discussions of the mind. The first is in the Transcendental Aesthetic,
the second is in what is usually called the Metaphysical Deduction (for
this term, see below). Then there are two discussions of it in the
first-edition TD, in parts 1 to 3 of Section 2 (A98 up to A110) and in
the whole of Section 3
 (A115-A127)[2]
 and two more in the second-edition TD, from B129 to B140 and from
B153 to B159, the latter seemingly added as a kind of supplement. The
seventh and last is found in the first edition version of Kant's
attack on the Paralogisms, in the course of which he says things of
the utmost interest about consciousness of and reference to
self. (What little was retained of these remarks in the second edition
was moved to the completely rewritten TD.) For understanding Kant on
the mind and self-knowledge, the first edition of *CPR* is far
more valuable than the second edition. Kant's discussion proceeds
through the following stages.


### 2.1 Transcendental Aesthetic




Kant calls the first stage the Transcendental
 Aesthetic.[3]
 It is about what space and time must be like, and how we must handle
them, if our experience is to have the spatial and temporal properties
that it has. This question about the necessary conditions of
experience is for Kant a 'transcendental' question and the
strategy of proceeding by trying to find answers to such questions is,
as we said, the strategy of transcendental argument.




Here Kant advances one of his most notorious views: that whatever it
is that impinges on us from the mind-independent world does not come
located in a spatial nor even a temporal matrix
(A37=B54fn.). Rather, it is the mind that organizes this
'manifold of raw intuition', as he called it, spatially and
temporally. The mind has two pure forms of intuition, space and time,
built into it to allow it to do so. ('Pure' means
'not derived from experience'.)




These claims are very problematic. For example, they invite the
question, in virtue of what is the mind constrained to locate a bit of
information at one spatial or temporal location rather than another?
Kant seems to have had no answer to this question (Falkenstein 1995;
Brook 1998). Most commentators have found Kant's claim that space and
time are only in the mind, not at all in the mind-independent world, to
be implausible.




The activity of locating items in the 'forms of
intuition', space and time, is one of the three kinds of what
Kant called synthesis and discussed in the chapter on the
Transcendental Deduction. It is not entirely clear how the two
discussions relate.


### 2.2 Metaphysical Deduction




The Aesthetic is about the conditions of experience, Kant's official
project. The chapter leading up to the Transcendental Deduction, The
Clue to the Discovery of All Pure Concepts of the Understanding (but
generally called the Metaphysical Deduction because of a remark that
Kant once made, B159) has a very different starting point.




Starting from (and, Bvii, taking for granted the adequacy of) Aristotelian
logic (the syllogisms and the formal concepts that Aristotle called categories), Kant proceeds by analysis to draw out the implications of these concepts and syllogisms for the conceptual structure (the "function of thought in judgment" (A70=B95)) within which all thought and experience must take place. The result is what Kant called the 
 Categories. That is to say, Kant tries to deduce the conceptual structure of experience from the components of Aristotelian logic.




Thus, in Kant's thought about the mind early in *CPR*, there
is not one central movement but two, one in the Transcendental
Aesthetic and the other in the Metaphysical Deduction. The first is a
move up from experience (of objects) to the necessary conditions of
such experience. The second is a move down from the Aristotelian functions
of judgment to the concepts that we have to use in judging, namely, the
Categories. One is inference up from experience, the other deduction
down from conceptual structures of the most abstract kind.


### 2.3 Transcendental Deduction, 1st Edition




Then we get to the second chapter of the Transcendental Logic, the
brilliant and baffling Transcendental Deduction (TD). Recall the two
movements just discussed, the one from experience to its conditions and
the one from Aristotelian functions of judgment to the concepts that we must
use in all judging (the Categories). This duality led Kant to his
famous question of right (*quid juris)* (A84=B116): with what
right do we apply the Categories, which are not acquired from
experience, to the contents of experience? (A85=B117). Kant's problem
here is not as arcane as it might seem. It reflects an important
question: How is it that the world as we experience it conforms to our
logic? In briefest form, Kant thought that the trick to showing how it
is *possible* for the Categories to apply to experience is to
show that it is *necessary* that they apply
 (A97).[4]





TD has two sides, though Kant never treats them separately. He once
called them the objective and the subjective deductions (Axvii). The
objective deduction is about the conceptual and other cognitive
conditions of having representations of objects. It is Kant's answer to
the *quid juris* question. Exactly how the objective deduction
goes is highly controversial, a controversy that we will sidestep here.
The subjective deduction is about what the mind, the "subjective
sources" of understanding (A97), must as a consequence be like.
The subjective deduction is what mainly interests us.




Kant argues as follows. Our experiences have objects, that is, they are about
something. The objects of our experiences are discrete, unified
particulars. To have such particulars available to it, the mind must
construct them based on sensible input. To construct them, the mind
must do three kinds of synthesis. It must generate temporal and spatial
structure (Synthesis of Apprehension in Intuition). It must associate
spatio-temporally structured items with other spatio-temporally
structured items (Synthesis of Reproduction in the Imagination). And it
must recognize items using concepts, the Categories in particular
(Synthesis of Recognition in a Concept). This threefold doctrine of
synthesis is one of the cornerstones of Kant's model of the mind. We
will consider it in more detail in the next Section.




The 'deduction of the categories' should now be
complete. Strangely enough, the chapter has only nicely got started. In
the first edition version, for example, we have only reached A106,
about one-third of the way through the chapter. At this point, Kant
introduces the notion of transcendental apperception for the first time
and the unity of such apperception, the unity of consciousness.
Evidently, something is happening (something, moreover, not at all well
heralded in the text). We will see what when we discuss Kant's doctrine
of synthesis below.




We can now understand in more detail why Kant said that the subjective
deduction is inessential (Axvii). Since the objective deduction is
about the conditions of representations having objects, a better name
for it might have been 'deduction of the
object'. Similarly, a better name for the subjective deduction
might have been 'the deduction of the subject' or
'the deduction of the subject's nature'. The latter
enquiry was inessential to Kant's main critical project because the
main project was to defend the synthetic *a priori* credentials
of physics in the objective deduction. From this point of view,
anything uncovered about the nature and functioning of the mind was a
happy accident.


### 2.4 Attack on the Paralogisms, 1st Edition




The chapter on the Paralogisms, the first of the three parts of Kant's
second project, contains Kant's most original insights into the nature
of consciousness of the self. In the first edition, he seems to have
achieved a stable position on self-consciousness only as late as this
chapter. Certainly his position was not stable in TD. Even his famous
term for consciousness of self, 'I think', occurs for the
first time only in the introduction to the chapter on the
Paralogisms. His target is claims that we know what the mind is
like. Whatever the merits of Kant's attack on these claims, in the
course of mounting it, he made some very deep-running observations
about consciousness and knowledge of self.




To summarize: in the first edition, TD contains most of what Kant
had to say about synthesis and unity, but little on the nature of
consciousness of self. The chapter on the Paralogisms contains most of
what he has to say about consciousness of self.


### 2.5 The Two Discussions in the 2nd-edition TD and Other Discussions




As we said, Kant rewrote both TD and the chapter on the Paralogisms
for the second edition of *CPR*, leaving only their
introductions intact. In the course of doing so, he moved the topic of
consciousness of self from the chapter on the Paralogisms to the
second discussion of the mind in the new TD. The new version of the
Paralogisms chapter is then built around a different and, so far as
theory of mind is concerned, much less interesting strategy. The
relationship of the old and new versions of the chapters is
complicated (Brook 1994, Ch. 9). Here we will just note that the
underlying doctrine of the mind does not seem to change very much.



*CPR* contains other discussions of the mind, discussions
that remained the same in both editions. The appendix on what Kant
called Leibniz' Amphiboly contains the first explicit discussion of an
important general metaphysical notion, numerical identity (being one
object at and over time), and contains the first *argument* in
*CPR* for the proposition that sensible input is needed for
knowledge. (Kant asserts this many times earlier but assertion is not
argument.) In the Antinomies, the discussion of the Second Antinomy
contains some interesting remarks about the simplicity of the soul and
there is a discussion of free will in the Solution to the Third
Antinomy. The mind also appears a few times in the Doctrine of Method,
particularly in a couple of glosses of the attack mounted against the
Paralogisms. (A784=B812ff is perhaps the most interesting.)




In other new material prepared for the second edition, we find a
first gloss on the topic of self-consciousness as early as the
Aesthetic (B68). The mind also appears in a new passage called the
Refutation of Idealism, where Kant attempts to tie the possibility of
one sort of consciousness of self to consciousness of permanence in
something other than ourselves, in a way he thought to be inconsistent
with Berkeleian idealism. This new Refutation of Idealism has often
been viewed as a replacement for the argument against the Fourth
Paralogism of the first edition. There are problems with this view, the
most important of which is that the second edition still has a separate
fourth Paralogism (B409). That said, though the new passage utilizes
self-consciousness in a highly original way, it says little that is new
about it.




Elsewhere in his work, the only sustained discussion of the mind and
consciousness is, as we said, his little, late *Anthropology from a
Pragmatic Point of View*. By 'anthropology' Kant meant
the study of human beings from the point of view of their
(psychologically-controlled) behaviour, especially their behaviour
toward one another, and of the things revealed in behaviour such as
character. Though Kant sometimes contrasted anthropology as a legitimate study
with what he understood empirical psychology to be, namely, psychology
based on introspective observation, he meant by anthropology something
fairly close to what we now mean by behavioural or experimental
psychology.


## 3. Kant's View of the Mind


### 3.1 Method




Turning now to Kant's view of the mind, we will start with a point
about method: Kant held surprisingly strong and not entirely
consistent views on the empirical study of the mind. The empirical
method for doing psychology that Kant discussed was introspection.





Sometimes he held such study to be hopeless. The key text on
psychology is in *The Metaphysical Foundations of Natural
Science*. There Kant tell us that "the empirical doctrine of
the soul ... must remain even further removed than chemistry from
the rank of what may be called a natural science proper"
(Ak. IV:471). (In Kant's defence, there was nothing resembling a
single unified theory of chemical reactions in his time.) The contents
of introspection, in his terms inner sense, cannot be studied
scientifically for at least five reasons.




First, having only one universal dimension and one that they are
only *represented* to have at that, namely, distribution in
time, the contents of inner sense cannot be quantified; thus no
mathematical model of them is possible. Second, "the manifold of
internal observation is separated only by mere thought". That is
to say, only the introspective observer distinguishes the items one
from another; there are no real distinctions among the items
themselves. Third, these items "cannot be kept separate" in
a way that would allow us to connect them again "at will",
by which Kant presumably means, according to the dictates of our
developing theory. Fourth, "another thinking subject [does not]
submit to our investigations in such a way as to be conformable to our
purposes" - the only thinking subject whose inner sense one
can investigate is oneself. Finally and most damningly, "even the
observation itself alters and distorts the state of the object
observed" (1786, Ak. IV:471). Indeed, introspection can be bad
for the health: it is a road to "mental illness"
('Illuminism and Terrorism', 1798, Ak. VII:133; see
161).




In these critical passages, it is not clear why he didn't respect what
he called anthropology more highly as an empirical study of the mind,
given that he himself did it. He did so elsewhere. In the
*Anthropology*, for example, he links
'self-observation' and observation of others and calls
them both sources of anthropology (Ak. VII:142-3).



 Whatever, no kind of empirical psychology can yield necessary truths
about the mind. In the light of this limitation, how *should*
we study the mind? Kant's answer was: transcendental method using
transcendental arguments (notions introduced earlier). If we cannot
observe the connections among the denizens of inner sense to any
purpose, we can study what the mind *must* be like and what
capacities and structures (in Kant's jargon, faculties) it
*must* have if it is to represent things as it does. With this
method we can find universally true, that is to say,
'transcendental' psychological propositions. We have
already seen what some of them are: minds must be able to synthesize
and minds must have a distinctive unity, for example. Let us turn now
to these substantive claims.


### 3.2 Synthesis and Faculties




We have already discussed Kant's view of the mind's handling of
space and time, so we can proceed directly to his doctrine of
synthesis. As Kant put it in one of his most famous passages,
"Concepts without intuitions are empty, intuitions without
concepts are blind" (A51=B75). Experience requires both percepts
and concepts. As we might say now, to discriminate, we need
information; but for information to be of any use to us, we must
organize the information. This organization is provided by acts of
synthesis.



> By *synthesis,* in its most general sense, I
> understand the act of putting different representations together, and
> of grasping what is manifold in them in one knowledge
> [A77=B103]



If the doctrine of space and time is the first major part of his
model of the mind, the doctrine of synthesis is the second. Kant
claimed, as we saw earlier, that three kinds of synthesis are required
to organize information, namely apprehending in intuition, reproducing
in imagination, and recognizing in concepts (A97-A105). Each of the
three kinds of synthesis relates to a different aspect of Kant's
fundamental duality of intuition and concept. Synthesis of
apprehension concerns raw perceptual input, synthesis of recognition
concerns concepts, and synthesis of reproduction in imagination allows
the mind to go from the one to the other. 




They also relate to three fundamental faculties of the mind. One is
the province of Sensibility, one is the province of Understanding, and
the one in the middle is the province of a faculty that has a far less
settled position than the other two, namely, Imagination (see
A120).




The first two, apprehension and reproduction, are inseparable; one
cannot occur without the other (A102). The third, recognition, requires
the other two but is not required by them. It seems that only the third
requires the use of concepts; this problem of non-concept-using
syntheses and their relationship to use of the categories becomes a
substantial issue in the second edition (see B150ff.), where Kant tries
to save the universality of the objective deduction by arguing that all
three kinds of syntheses are required to represent objects.




Acts of synthesis are performed on that to which we are passive in
experience, namely intuitions (*Anschauungen).* Intuitions are
quite different from sense-data as classically understood; we can
become conscious of intuitions only after acts of synthesis and only by
inference from these acts, not directly. Thus they are something more
like theoretical entities (better, events) postulated to explain
something in what we do recognize. What they explain is the
non-conceptual element in representations, an element over which we
have no control. Intuitions determine how our representations will
serve to confirm or refute theories, aid or impede our efforts to reach
various goals.


#### 3.2.1 Synthesis of Apprehension in Intuition




The synthesis of apprehension is somewhat more shadowy than the
other two. In the second edition, the idea does not even appear until
SS26, i.e., late in TD. At A120, Kant tells us that apprehending
impressions is taking them up into the activity of imagination, i.e.,
into the faculty of the mind that becomes conscious of images. He tells
us that we can achieve the kind of differentiation we need to take them
up only "in so far as the mind distinguishes the time in the
sequence of one impression upon another" (A99). Kant uses the
term 'impression' (*Eindrucke*) rarely; it seems to
be in the same camp as 'appearance' (*Erscheinung*)
and 'intuition' (*Anschauung*).




The idea behind the strange saying just quoted seems to be this.
Kant seems to have believed that we can become conscious of only one
new item at a time. Thus a group of simultaneous
'impressions' all arriving at the same time would be
indistinguishable, "for each representation
[*Vorstellung*], *in so far as it is contained in a single
moment*, can never be anything but absolute unity" (A99).
Kant's use of *Vorstellung*, with its suggestion of synthesized,
conceptualized organization, may have been unfortunate, but what I
think he meant is this. Prior to synthesis and conceptual organization,
a manifold of intuitions would be an undifferentiated unit, a seamless,
buzzing confusion. Thus, to distinguish one impression from another, we
must give them separate locations. Kant speaks only of temporal
location but he may very well have had spatial location in mind,
too.




The synthesis of apprehension is closely related to the
Transcendental Aesthetic. Indeed, it is the doing of what the Aesthetic
tells us that the mind has to be able to do with respect to locating
items in time and space (time anyway).


#### 3.2.2 Synthesis of Reproduction in Imagination




The synthesis of reproduction in imagination has two elements, a
synthesis proper and associations necessary for performing that
synthesis. (Kant explicitly treats them as separate on A125:
"recognition, reproduction, association, apprehension".)
Both start from the appearances, as Kant now calls them, which the
synthesis of apprehension has located in time. At first glance, the
synthesis of reproduction looks very much like
 memory;
 however, it is actually quite different from memory. It is a matter
of retaining earlier intuitions in such a way that certain other
representations can "bring about a transition of the mind"
to these earlier representations, even in the absence of any current
representation of them (A100). Such transitions are the result of the
setting up of associations (which, moreover, need not be conscious)
and do not require memory. Likewise, no recognition of any sort need
be involved; that the earlier representations have become associated
with later ones is not something that we need recognize. Memory and
recognition are the jobs of synthesis of recognition, yet to come.




To our ears now, it is a little strange to find Kant calling this
activity of reproduction and the activity of apprehension acts of
*imagination*. Kant describes the function he had in mind as
"a blind but indispensable function of the soul"
(A78=B103), so he meant something rather different from what we now
mean by the term 'imagination' (A120 and fn.). For Kant,
imagination is a connecting of elements by forming an image:
"... imagination has to bring the manifold of intuitions
into the form of an image" (A120). If 'imagination'
is understood in its root sense of image-making and we see imagination
not as opposed to but as part of perception, then Kant's choice of term
becomes less peculiar.


#### 3.2.3 Synthesis of Recognition in a Concept




The third kind of synthesis is synthesis of recognition in a
concept. To experience objects for Kant, first I have to relate the
materials out of which they are constructed to one another temporally
and spatially. They may not require use of concepts. Then I have to
apply at least the following kinds of concepts: concepts of number, of
quality, and of modality (I am experiencing something real or
fictitious). These are three of the four kinds of concepts that Kant
had identified as Categories. Note that we have so far not mentioned
the fourth, relational concepts.




In Kant's view, recognition requires memory; reproduction is not
memory but memory does enter now. The argument goes as follows.



> [A merely reproduced] manifold of representation would
> never ... form a whole, since it would lack that unity which only
> consciousness can impart to it. If, in counting, I forget that the
> units, which now hover before me, have been added to one another in
> succession, I should never know that a total is being produced through
> this successive addition of unit to unit ... [A103; see
> A78=B104].




In fact, as this passage tells us, synthesis into an object by an
act of recognition requires two things. One is memory. The other is
that something in the past representations must be recognized *as
related to* present ones. And to recognize that earlier and later
representations are both representing a single object, we must use a
concept, a rule (A121, A126). In fact, we must use a number of
concepts: number, quality, modality, and, of course, the specific
empirical concept of the object we are recognizing.




Immediately after introducing recognition, Kant brings apperception
and the unity of apperception into the discussion. The acts by which we
achieve recognition under concepts are acts of apperception. By
'apperception', Kant means the faculty or capacity for
judging in accord with a rule, for applying concepts. Apperceiving is
an activity necessary for and parallel to perceiving (A120). This is
one of the senses in which Leibniz used the term, too. To achieve
recognition of a unified object, the mind must perform an act of
judgment; it must find how various represented elements are connected
to one another. This judgment is an act of apperception. Apperception
is the faculty that performs syntheses of recognition (A115). Note that
we are not yet dealing with *transcendental* apperception.




To sum up: For experiences to have objects, acts of recognition that
apply concepts to spatio-temporally ordered material are required.
Representation requires recognition. Moreover, objects of
representation share a general structure. They are all some number of
something, they all have qualities, and they all have an
existence-status. (Put this way, Kant's claim that the categories are
required for knowledge looks quite plausible.)


### 3.3 Synthesis: A 90deg Turn




With the synthesis of recognition, TD should be close to complete.
Kant merely needs to argue that these concepts must include the
categories, which he does at A111, and that should be that.




But that is not that. In fact, as we said earlier, we are only about
one-third of the way through the chapter. The syntheses of
apprehension, reproduction, and recognition of single objects march in
a single temporal/object-generational line. Suddenly at A106 Kant makes
a kind of 90o turn. From the generation of a representation
of individual objects of experience *over time*, he suddenly
turns to a form of recognition that requires the unification and
recognition of multiple objects existing *at the same time.* He
moves from acts of recognition of individual objects to unified acts of
recognition of multiple objects which "stand along side one
another in one experience" (A108). This 90o turn is a
pivotal moment in TD and has received less attention than it
deserves.




The move that Kant makes next is interesting. He argues that the
mind could not use concepts so as to have unified objects of
representation *if its consciousness were not itself unified*
(A107-108). Why does consciousness and its unity appear here? We have
been exploring what is necessary to have experience. Why would it
matter if, in addition, unified consciousness were necessary? As Walker
(1978, p. 77) and Guyer (1987, pp. 94-5) have shown, Kant did not need
to start from *anything* about the mind to deduce the
Categories. (A famous footnote in *The Metaphysical Foundations of
Natural Science* [Ak. IV:474fn.] is Kant's best-known comment on
this issue.) So why does he suddenly introduce unified
consciousness?




So far Kant has 'deduced' only three of the four kinds
of categorical concepts, number, quality, and modality. He has said
nothing about the relational categories. For Kant, this would have been
a crucial gap. One of his keenest overall objectives in *CPR* is
to show that physics is a real science. To do this, he thinks that he
needs to show that we must use the concept of causality in experience.
Thus, causality is likely the category that he cared more about than
all the other categories put together. Yet up to A106, Kant has said
nothing about the relational categories in general or causality in
particular. By A111, however, Kant is talking about the use of the
relational categories and by A112 causality is front and centre. So it
is natural to suppose that, in Kant's view at least, the material
between A106 and A111 contains an argument for the necessity of
applying the relational categories, even though he never says so.




Up to A106, Kant has talked about nothing but normal individual
objects: a triangle and its three sides, a body and its shape and
impenetrability. At A107, he suddenly begins to talk about tying
together multiple represented objects, indeed "all possible
appearances, which can stand alongside one another in one
experience" (A108). The solution to the problem of showing that
we have to use the category of causality must lie somewhere in this
activity of tying multiple objects together.




The passage between A106 and A111 is blindingly difficult. It takes
up transcendental apperception, the unity and identity of the mind, and
the mind's consciousness of itself as the subject of all its
representations (A106-108). I think that this passage introduces either
a new stage or even a new starting point for TD. Here many commentators
(Strawson, Henrich, Guyer) would think immediately of
self-consciousness. Kant did use consciousness of self as a starting
point for deductions, at B130 in the B-edition for example. But that is
not what appears here, not in the initial paragraphs anyway.




What Kant does say is this. Our experience is "one
experience"; "all possible appearances ... stand
alongside one another in one experience" (A108). We have
"one and the same general experience" of "all
... the various perceptions" (A110), "a connected
whole of human knowledge" (A121). Let us call this general
experience a *global representation*.



*Transcendental apperception* (hereafter TA) now enters. It
is the ability to tie 'all appearances' together into
'one experience'.



> This transcendental unity of apperception forms out of all
> possible appearances, which can stand alongside one another in one
> experience, a connection of all these representations according to
> laws. [A108]




It performs a "synthesis of all appearances according to
concepts", "whereby it subordinates all synthesis of
apprehension ... to a transcendental unity" (A108). This, he
thought, requires unified consciousness. Unified consciousness is
required for another reason, too. Representations



> can [so much as] represent something to me only in so far
> as they belong with all others to one consciousness. Therefore, they
> must at least be capable of being so connected [A116].




The introduction of unified consciousness opens up an important new
opportunity. Kant can now explore the necessary conditions of conscious
content being unified in this way. To make a long story short, Kant now
argues that conscious content could have the unity that it does only if
the contents themselves are tied together
 causally.[5]





With this, his deduction of the relational categories is complete
and his defence of the necessity of physics is under way. The notion of
unified consciousness to which Kant is appealing here is interesting in
its own right, so let us turn to it
 next.[6]



### 3.4 Unity of Consciousness




For Kant, consciousness being unified is a central feature of the
mind, our kind of mind at any rate. In fact, being a single integrated
group of experiences (roughly, one person's experiences) requires two
kinds of unity.


1. The experiences must have a single common subject (A350);

and,
2. The consciousness that this subject has of represented objects
and/or representations must be unified.




The first requirement may look trivial but it is not. For Hume, for
example, what makes a group of experiences one person's experiences is
that they are associated with one another in an appropriate way (the
so-called bundle theory), not that they have a common subject. The need
for a subject arises from two straightforward considerations:
representations not only represent something, they represent it to
someone; and, representations are not given to us - to become a
representation, sensory inputs must be processed by an integrated
cognitive system. Kant may have been conscious of both these points,
but beyond identifying the need, he had little to say about what the
subject of experience might be like, so we will say no more about it.
(We will, however, say something about what its consciousness of itself
is like later.)




Kant seems to have used the terms 
 'unity of consciousness' (A103)
 and 'unity of apperception' (A105, A108) 
interchangeably. The well-known argument at the beginning of the first
edition attack on the second paralogism (A352) focuses on this unity
at a given time (among other things) and what can (or rather, cannot)
be inferred from this about the nature of the mind (a topic to which
we will return below). The attack on the third paralogism focuses on
what can be inferred from unified consciousness over time. These are
all from the first edition of *CPR*. In the second edition,
Kant makes remarks about unity unlike anything in the first edition,
for example, "this unity ... is not the category of
unity" (B131). The unity of consciousness and Kant's
views on it are complicated issues but some of the most important
points include the following.




By 'unity of consciousness', Kant seems to have the
following in mind: I am conscious not only of single experiences but of
a great many experiences at the same time. The same is true of actions;
I can do and be conscious of doing a number of actions at the same
time. In addition to such synchronic unity, many global
representations, as we called them, display temporal unity: current
representation is combined with retained earlier representation.
(Temporal unity is often a feature of synthesis of recognition.) Any
representation that we acquire in a series of temporal steps, such as
hearing a sentence, will have unity across time (A104; A352).




Kant himself did not explicate his notion of unified consciousness
but here is one plausible articulation of the notion at work in his
writings.



> The unity of consciousness =*df.* (i) a single act
> of consciousness, which (ii) makes one conscious of a number of
> representations and/or objects of representation in such a way that to
> be conscious by having any members of this group is also to be
> conscious by having others in the group and of at least some of them as
> a group.




As this definition makes clear, consciousness being unified is more
than just being one state of consciousness. Unified consciousness is
not just singular, it is unified.




Kant placed great emphasis on the unity of consciousness, both
positively and negatively. Positively, he held that conceptualized
representation has to be unified both at and across time. Negatively,
from a mind having unified consciousness, he held that nothing follows
concerning its composition, its identity, especially its
 identity across time,
 nor its materiality or immateriality. He argued these points in his
attacks on the second, third and fourth Paralogisms.


## 4. Consciousness of Self and Knowledge of Self




Many commentators hold that consciousness of self is central to the
Critical philosophy. There is reason to question this: unified
consciousness is central, but consciousness of self? That is not so
clear. Whatever, the topic is intrinsically interesting and Kant
achieved some remarkable insights into it. Strangely, none of his
immediate successors took them up after his death and they next
appeared at the earliest in Wittgenstein (1934-5) and perhaps not until
Shoemaker (1968). Kant never discussed consciousness of self in its own
right, only in the context of pursuing other objectives, and his
remarks on the topic are extremely scattered. When we pull his various
remarks together, we can see that Kant advanced at least seven major
theses about consciousness of and
 knowledge of self.
 We will consider them one-by-one.


### 4.1 Thesis 1: Two Kinds of Consciousness of Self




The first thesis:


1. There are two kinds of consciousness of self: consciousness of
oneself and one's psychological states in inner sense and
consciousness of oneself and one's states via performing acts of
apperception.




Kant's term for the former was 'empirical
self-consciousness'. A leading term for the latter was
'transcendental apperception' (TA). (Kant used the term
'TA' in two very different ways, as the name for a faculty
of synthesis and as the name for what he also referred to as the
'I think', namely, one's consciousness of oneself as
subject.) Here is a passage from the *Anthropology* in which
Kant distinguishes the two kinds of consciousness of self very
clearly:



> ... *the "I" of reflection*
> contains no manifold and is always the same in every judgment ...
> *Inner experience*, on the other hand, contains the matter of
> consciousness and a manifold of empirical inner intuition: ...
> [1798, Ak. VII:141-2, emphases in the original].




The two kinds of consciousness of self have very different
sources.




The source of empirical self-consciousness is what Kant called inner
sense. He did not work out his notion of inner sense at all well. Here
are just a few of the problems. Kant insists that all representational
states are in inner sense, including those representing the objects of
outer sense (i.e., spatially located objects):



> Whatever the origins of our representations, whether they
> are due to the influence of outer things, or are produced through inner
> causes, whether they arise *a priori*, or being appearances have
> an empirical origin, they must all, as modifications of the mind,
> belong to inner sense. [A98-9]




However, he also says that the object of inner sense is the soul,
the object of outer sense the body (including one's own). He comes
close to denying that we can be conscious of the denizens of inner
sense--they do not represent inner objects and have no manifold
of their own. Yet he also says that we can be conscious of them --
representations can themselves be objects of representations, indeed,
representations can make us conscious of themselves. In its role as a
form of or means to consciousness of self, apperception ought to be
part of inner sense. Yet Kant regularly contrasted apperception, a
means to consciousness of oneself and one's acts of thinking, with
inner sense as a means to consciousness of--what? Presumably,
particular representations: perceptions, imaginings, memories, etc.
Here is another passage from the *Anthropology*:



> SS24. Inner sense is not pure apperception,
> consciousness of what we are doing; for this belongs to the power of
> thinking. It is, rather, consciousness of what we undergo as we are
> affected by the play of our own thoughts. This consciousness rests on
> inner intuition, and so on the relation of ideas (as they are either
> simultaneous or successive). [1798, Ak. VII:161]




Kant makes the same distinction in *CPR*:



> ... the I that I think is distinct from the I that it,
> itself, intuits ...; I am given to myself beyond that which is
> given in intuition, and yet know myself, like other phenomena, only as
> I appear to myself, not as I am ... [B155].




Since most of Kant's most interesting remarks about consciousness of
and knowledge of self concern consciousness of oneself, the 'I of
reflection' via acts of apperception, we will focus on it, though empirical consciousness
of self will appear again briefly from time to time.


### 4.2 Thesis 2: Representational Base of Consciousness of Oneself and One's States




How does apperception give rise to consciousness of oneself and one's
states? In the passage just quoted from the *Anthropology,*
notice the phrase "consciousness of what we are doing"
-- *doing.* The way in which one becomes conscious of an
*act of representing* is not by receiving intuitions but by
doing it: "synthesis ..., as an act, ... is conscious
to itself, even without sensibility" (B153); "...
this representation is an act of *spontaneity*, that is, it
cannot be regarded as belonging to sensibility" (B132).




Equally, we can be conscious of ourselves as subject merely by doing
acts of representing. No further representation is needed.



> Man, ... who knows the rest of nature solely through
> the senses, knows himself also through pure apperception; and this,
> indeed, in acts and inner determinations which he cannot regard as
> impressions of the senses [A546=B574].




How does one's consciousness of oneself in one's acts of
representing work? Consider the sentence:



> I am looking at the words on the screen in front of
> me.




Kant's claim seems to be that the representation of the words on the
screen is all the experience I need to be conscious not just of the
words and the screen but also of the act of seeing them and of
*who* is seeing them, namely, me. A single representation can do
all three jobs. Let us call an act of representing that can make one
conscious of its object, itself and oneself as its subject the
*representational base* of consciousness of these three
 items.[7]
 Kant's second major thesis is,


2. Most ordinary representations generated by most ordinary acts of
synthesis provide the representational base of consciousness of
oneself and one's states.




Note that this representational base is the base not only of
consciousness of one's representational states. It is also the base of
consciousness of oneself as the subject of those states--as the
thing that has and does them. Though it is hard to know for sure,
Kant would probably have denied that consciousness of oneself in inner
sense can make one conscious of oneself as subject, of oneself as
oneself, in this way. 




For Kant, this distinction between consciousness of oneself and one's
states by doing acts of synthesis and consciousness of oneself and
one's states as the objects of particular representations is of
fundamental importance. When one is conscious of oneself and one's
states by doing cognitive and perceptual acts, one is conscious of
oneself as spontaneous, rational, self-legislating, free--as
the doer of deeds, not just as a passive receptacle for
representations: "I exist as an intelligence which is conscious
solely of its power of combination" (B158-159), of "the
activity of the self" (B68) (Sellars, 1970-1; Pippin, 1987).




So far we have focussed on individual representations. For Kant,
however, the representations that serve as the representational base of
consciousness of oneself as subject are usually much
'bigger' than that, i.e., contain multiple objects and
often multiple representations of them tied together into what Kant
called 'general experience'.



> When we speak of different experiences, we can refer only
> to the various perceptions, all of which belong to one and the same
> general experience. This thoroughgoing synthetic unity of perceptions
> is the form of experience; it is nothing less than the synthetic unity
> of appearances in accordance with concepts [A110].




This general experience is the global representation introduced
earlier. When I am conscious of many objects and/or representations of
them as the single object of a single global representation, the latter
representation is all the representation I need to be conscious not
just of the global object but also of myself as the common subject of
all the constituent representations.



> The mind could never think its identity in the manifoldness
> of its representations... if it did not have before its eyes the
> identity of its act, whereby it subordinates all [the manifold]
> ... to a transcendental unity... [A108].




I am conscious of myself as the single common subject of a certain
group of experiences by being conscious of "the identity of the
consciousness in ... conjoined ... representations"
(B133).


### 4.3 Thesis 3: Consciousness in Inner Sense is Only of How One Appears to Oneself




Neither consciousness of self by doing apperceptive acts nor empirical
consciousness of self as the object of particular representations
yields knowledge of oneself as one is. On pain of putting his right to
believe in immortality as an article of faith at risk, Kant absolutely
had to claim this. As he put it,



> it would be a great stumbling block, or rather would be the
> one unanswerable objection, to our whole critique if it were possible
> to prove *a priori* that all thinking beings are in themselves
> simple substances. [B409]




The same would hold for all other properties of thinking beings.
Since Kant also sometimes viewed immortality, i.e., personal
continuity beyond death, as a foundation of morality, morality could
also be at risk. So Kant had powerful motives to maintain that one
does not know oneself as one is. Yet, according to him, we seem to
know at least some things about ourselves, namely, how we must
function, and it would be implausible to maintain that one never
conscious of one's real self at all. Kant's response to these pressures
is ingenious.




First, he treats inner sense: When we know ourselves as the object of
a representation in inner sense, we "know even ourselves only
.. as appearance ..." (A278).



> Inner ... sense ... represents to consciousness even our
> own selves only as we appear to ourselves, not as we are in ourselves.
> For we intuit ourselves only as we are inwardly *affected* [by
> ourselves] (B153).




This is the third thesis:


3. In inner sense, one is conscious of oneself only as one appears to
oneself, not as one is.




So when we seem to be directly conscious of features of ourselves,
we in fact have the same kind of consciousness of them as we have of features
of things in general--we appear to ourselves to be like this,
that or the other, in just the way that we know of any object only as
it appears to us.




Then he turns to consciousness of oneself and one's states by doing
apperceptive acts. This is a knottier problem. Here we will consider
only consciousness of oneself as subject. Certainly by the second
edition, Kant had come to see how implausible it would be to maintain
that one has no consciousness of oneself, one's real self, at all when
one is conscious of oneself as the subject of one's experience, agent
of one's acts, by having these experiences and doing those acts. In
the 2nd edition, he reflects this sensitivity as early as
B68; at B153, he goes so far as to say that an apparent contradiction
is involved. 




Furthermore, when we are conscious of ourselves as subject and agent
by doing acts of apperceiving, we do *appear* to ourselves to
be substantial, simple and continuing. He had to explain these
appearances away; doing so was one of his aims, indeed, in his attacks on
the second and third Paralogisms. Thus, Kant had strong motives to
give consciousness of self as subject special treatment. The view that proposes is puzzling. I am not consciousness of myself as I appear to myself, nor as I am in myself but only "that I am" (B157). To understand what he might mean here, we need a couple of intermediate theses. They contain the remarkable insights into reference to and consciousness of self mentioned earlier.


### 4.4 Thesis 4: Referential Machinery of Consciousness of Self




Kant generated the special treatment he needed by focussing first on
reference to self. Here are some of the things that he said about
reference to oneself as subject. It is a consciousness of self in
which "nothing manifold is given." (B135). In the kind of
reference in which we gain this consciousness of self, we
"denote" but do not "represent" ourselves
(A382). We designate ourselves without noting "any quality
whatsoever" in ourselves (A355). This yields his fourth thesis
about consciousness of and knowledge of self.


4. The referential machinery used to obtain consciousness of self as
subject requires no identifying (or other) ascription of properties to
oneself.




This is a remarkably penetrating claim; remember, the study of
reference and semantics generally is usually thought to have begun only
with Frege. Kant is anticipating two important theses about reference
to self that next saw the light of day only 200 years later.


1. In certain kinds of consciousness of self, one can be conscious of
something as oneself without identifying it (or anything) as oneself
via properties that one has ascribed to the thing (self-reference
without identification) (Shoemaker
 1968),[8]
  


and,
2. In such cases, first-person
 indexicals
 (I, me, my, mine) cannot be analysed out in favour of anything else,
in particular anything descriptionlike (the essential indexical)
(Perry 1979).




Was Kant actually aware of (1) and/or (2) or had he just stumbled
across something that later philosophers recognized as significant?




One standard argument for (1) goes as follows:



> My use of the word 'I' as the subject of
> [statements such as 'I feel pain' or 'I see a
> canary'] is not due to my having identified as myself something
> [otherwise recognized] of which I know, or believe, or wish to say,
> that the predicate of my statement applies to it [Shoemaker 1968,
> pp.558].




A standard argument for (2), that certain indexicals are essential,
goes as follows. To know that *I* wrote a certain book a few
years ago, it is not enough to know that someone over six feet tall
wrote that book, or that someone who teaches philosophy at a particular
university wrote that book, or ... or ... or ... , for I
could know all these things without knowing that it was *me* who
has these properties (and I could know that it *was* me who
wrote that book and not know that any of these things are properties of
me). As Shoemaker puts it,



> ... no matter how detailed a token-reflexive-free
> description of a person is, ... it cannot possibly entail that I
> am that person [1968, pp. 560].




Kant unquestionably articulated the argument for (1):



> In attaching 'I' to our thoughts, we designate
> the subject only transcendentally ... without noting in it any
> quality whatsoever--in fact, without knowing anything of it
> either directly or by inference [A355].




This *transcendental designation,* i.e., referring to oneself
using 'I' without 'noting any quality' in
oneself, has some unusual features. One can refer to oneself in a
variety of ways, of course: as the person in the mirror, as the person
born on such and such a date in such and such a place, as the first
person to do *X*, and so on, but one way of referring to oneself
is special: it does not require identifying or indeed any ascription to
oneself. So Kant tells
 us.[9]




The question is more complicated with respect to (2). We cannot go
into the complexities here (see Brook 2001). Here we will just note
three passages in which Kant may be referring to the essential
indexical or something like it.



> The subject of the categories cannot by thinking the
> categories [i.e. applying them to objects] acquire a concept of itself
> as an object of the categories. For in order to think them, its pure
> self-consciousness, which is what was to be explained, must itself be
> presupposed. [B422]




The phrase 'its pure self-consciousness' seems to refer
to consciousness of oneself as subject. If so, the passage may be
saying that judgments about oneself, i.e., ascriptions of properties to
oneself, 'presuppose ... pure self-consciousness',
i.e., consciousness of oneself via an act of ascription-free
transcendental designation.




Now compare this, "it is ... very evident that I cannot
know as an object that which I must presuppose to know any object
... ." (A402), and this,



> Through this I or he or it (the thing) which thinks,
> nothing further is represented than a transcendental subject of the
> thoughts = *X*. It is known only through the thoughts which are
> its predicates, and of it, apart from them, we cannot have any concept
> whatsoever, but can only revolve in a perpetual circle, since any
> judgment upon it has always already made use of its representation.
> [A346=B404]




The last clause is the key one: "any judgment upon it has
always already made use of its representation". Kant seems to be
saying that to know that anything is true of me, I must first know that
it is me of whom it is true. This is something very like the essential
indexical claim.




If reference to self takes place without 'noting any
properties' of oneself, the consciousness that results will also
have some special features.


### 4.5 Thesis 5: No Manifold in Consciousness of Self




The most important special feature is that, in this kind of
consciousness of self, one is not, or need not be, conscious of any
properties of oneself, certainly not any particular properties. One has
the same consciousness of self no matter what else one is conscious of
-- thinking, perceiving, laughing, being miserable, or whatever.
Kant expressed the thought this way,



> through the 'I', as simple representation,
> nothing manifold is given. [B135]




And this,



> the I that I think is distinct from the I that it ...
> intuits ...; I am given to myself beyond that which is given in
> intuition. [B155]




We now have the fifth thesis to be found in Kant:


5. When one is conscious of oneself as subject, one has a bare
consciousness of self in which "nothing manifold is
given."




Since, on Kant's view, one can refer to oneself as oneself without knowing any properties of oneself, not just identifying properties, 'non-ascriptive reference to self' might capture what is special about this form of consciousness of self better than Shoemaker's 'self-reference
without identification'.


### 4.6 Thesis 6: Consciousness of Self is not Knowledge of Self




Transcendental designation immediately yields the distinction that
Kant needs to allow that one is conscious of oneself as one is, not
just of an appearance of self, and yet deny knowledge of oneself as one
is. If consciousness of self ascribes nothing to the self, it can be a
"bare ... consciousness of self [as one is]" and yet
yield no knowledge of self--it is "very far from being a
knowledge of the self" (B158). This thesis returns us to
consciousness of self as subject:


6. When one is conscious of oneself as subject, one's bare
consciousness of self yields no knowledge of self.




In Kant's own work, he then put the idea of transcendental
designation to work to explain how one can appear to oneself to be
substantial, simple and persisting without these appearances reflecting
how one actually is. The reason that one appears in these ways is not
that the self is some strange, indefinable being. It is because of the
kind of referring that we do to become conscious of oneself as subject.
Given how long ago he worked, Kant's insights into this kind of
referring are nothing short of amazing.


### 4.7 Thesis 7: Conscious of Self as Single, Common Subject of Experience




The last of Kant's seven theses about consciousness of self is an
idea that we already met when we discussed the unity of
consciousness:


7. When we are conscious of ourselves as subject, we are conscious of
ourselves as the "single common subject" *[CPR,*
A350] of a number of representations.




What Kant likely had in mind is nicely captured in a remark of
Bennett's (1974, p. 83): to think of myself as a plurality of things is
to think of *my* being conscious of this plurality, "and
that pre-requires an undivided *me*." Unlike one of anything else, it is not optional that I think of myself as one subject across a
variety of experiences (A107).


## 5. Knowledge of the Mind




The remarks just noted about 'bare consciousness' and so
on by no means exhaust the concerns that can be raised about Kant and
what we can know about the mind. His official view has to be: nothing
-- about the mind's structure and what it is composed of, at any
rate, we can know nothing. As we have seen, Kant not only maintained
this but did some ingenious wiggling to account for the apparent
counter-evidence. But that is not the end of the story, for two
reasons.




First, whatever the commitments of his philosophy, Kant the person
believed that the soul is simple and persists beyond death; he found
materialism utterly repugnant (1783, Ak. IV, end of SS46). This is
an interesting psychological fact about Kant but needs no further
discussion.




Second and more importantly, Kant in fact held that we *do*
have knowledge of the mind as it is. In particular, we know that it has
forms of intuition in which it must locate things spatially and
temporally, that it must synthesize the raw manifold of intuition in
three ways, that its consciousness must be unified, and so on --
all the aspects of the model examined above.




To square his beliefs about what we cannot know and what we do know
about the mind, Kant could have made at least two moves. He could have
said that we know these things only 'transcendentally',
that is to say, by inference to the necessary conditions of experience.
We do not know them directly, in some sense of 'directly',
so we don't have intuitive, i.e., sense-derived knowledge of them. Or
he could have said that ontological neutrality about structure and
composition is compatible with knowledge of function. As we saw, Kant's
conception of the mind is functionalist--to understand the mind,
we must study what it does and can do, its functions--and the
doctrine that function does not dictate form is at the heart of
contemporary functionalism. According to functionalism, we can gain
knowledge of the mind's functions while knowing little or nothing about
how the mind is built. Approached this way, Kant's view that we know
*nothing* of the structure and composition of the mind would
just be a radical version of this functionalist idea. Either move would
restore consistency among his various claims about knowledge of the
mind.


## 6. Where Kant Has and Has Not Influenced Contemporary Cognitive Research




We will close by returning to the question of Kant's relationship to
contemporary cognitive research. As we saw, some of Kant's most
characteristic doctrines about the mind are now built into the very
foundations of cognitive science. We laid out what they were.
Interestingly, some of the others have played little or no role.




Consider the two forms of Synthesis of Recognition in a Concept. In
the form of binding, the phenomenon that he had in mind in the first
kind of synthesis is now widely studied. Indeed, one model, Anne
Treisman's (1980) three-stage model, is very similar to all three
stages of synthesis in Kant. According to Treisman and her colleagues,
object recognition proceeds in three stages: first feature detection,
then location of features on a map of locations, and then integration
and identification of objects under concepts. This compares directly to
Kant's three-stage model of apprehension of features, association of
features (reproduction), and recognition of integrated groups of under
concepts (A98-A106). However, Kant's second kind of recognition under
concepts, the activity of tying multiple representations together into
a global representation (A107-14), has received little attention.




The same was true until recently of the
 unity of consciousness
 and Kant's work on it. However, this is changing. In the past twenty
years, the unity of consciousness has come back onto the research
agenda and there are now hundreds of papers and a number of books on
the topic. However, claims such as Kant's that a certain form of
synthesis and certain links among the contents of experience are
required for unity continue to be ignored in cognitive science, though
a few philosophers have done some work on them (Brook 2004). The same
is true of Kant's views on consciousness of self; cognitive science
has paid no attention to non-ascriptive identification of self and the
idea of the essential indexical. Here, too, a few philosophers have
worked on these issues, apparently without knowing of Kant's
contribution (Brook & DeVidi, 2001), but not cognitive
scientists.




In short, the dominant model of the mind in contemporary cognitive
science is Kantian, but some of his most distinctive contributions have
not been taken into it (Brook, 2004).