AI & Soc (1990) 4:39-50
© 1990 Springer-Verlag London Limited
AI & SOCIETY
Thinking Persons and Cognitive Science
Martin Davies
Philosophy Department, Birkbeck College, Malet Street, London WC1E 7HX, UK
Abstract. Cognitive psychology and cognitive science are concerned with a domain of
cognition that is much broader than the realm of judgement, belief, and inference. The
idea of states with semantic content is extended far beyond the space of reasons and
justification. Within this broad class of states we should, however, differentiate between
the states distinctive of thinking persons - centrally, beliefs, desires, and intentions - and
other states. The idea of consciousness does not furnish a principle of demarcation. But the
distinction between states whose content is conceptualized by the person whose states they
are and states for which this is not so is more promising. This principle of demarcation
contains the seeds of a problem for distributed connectionism. The article ends with some
more general reflections about cognitive science.
Keywords: Cognition; Cognitive science; Concepts; Connectionism; Consciousness;
Content
There is a familiar distinction between perception and cognition. According to
that distinction, the realm of cognition is, roughly, that of thinking: judgement,
belief, and inference. In this familiar usage of the term, cognition has as its
paradigm cases believing and deciding on the basis of reasons. The space of
cognition is the space of reasons and justification; the cognitive realm is the realm
of propositional attitudes, governed by the norms of rationality. In short,
cognition is what makes us thinking persons.
What prospects or problems does this cognitive realm present for the
connectionist programme? More generally, what are the chances that cognitive
science will illuminate the realm of thought and inference?
Cognitive science actually concerns itself with a much broader domain, which
also includes early stages of perceptual processing, for example. We need a
principle for marking out, within this broad domain, the narrower realm that is
characteristic of thinking beings. The main argument of this article is that the
correct principle of demarcation contains the seeds of a problem for distributed
connectionism in the style of Smolensky (1988). The article ends with some more
general reflections about cognitive science.
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Martin Davies
Extending Content
The disciplines of cognitive psychology and cognitive science are concerned with
a domain that is very much broader than the realm of judgement, belief, and
inference. Absolutely typical examples of cognitive psychological research
concern the processes implicated in face recognition, or visual word recognition,
or reading aloud, or the experience of depth resulting from binocular disparity:
processes that fall squarely outside the space of reasons and justification.
This point is probably quite obvious; but let me labour it nevertheless. Take the
case of visual word recognition. The final upshot of a piece of word recognition
may well be a judgement, and a b e l i e f - the belief, say, that this is the word
"doctor" on the screen before me. But competing theories about the processes
involved in visual word recognition- whether it be logogens, or lexical search, or
cohorts, or threshold bias - are not theories about a subject's reasons for his
belief. Indeed, in a clear sense, the subject has no reason for his belief: he simply
takes at face value his experience as of the word "doctor" there on the screen in
front of him. We could make similar remarks about the other examples.
Chomsky's work on knowledge of language provides yet a further example of
research in this broad cognitive domain - once again, extending far beyond the
space of reasons. In expressing his claims, Chomsky sometimes uses the term
"cognize" (1980, pp. 69-70), with the intention that this should be much more
inclusive than any propositional attitude verb such as "believe", or indeed
"know" in the everyday sense. Thus, ordinary language users know - in the
familiar everyday sense involving belief- some facts about, for example, whether
certain strings are grammatical, and what various complete sentences mean.
Since "cognize" is supposed to be a more inclusive term than "believe", language
users also cognize these facts. But, in addition, they cognize facts that they do not
believe or even contemplate: facts stated by the rules or principles of a grammar,
from which the workaday facts follow.
These pieces of cognizing (or tacit knowledge) lie behind a language user's
judgements and beliefs about grammatically and about meaning; they are
causally antecedent to those judgements. But they in no way constitute the
language user's reasons for what he believes. The typical unreflective language
user simply takes at face value his impressions of grammaticality and meaning.
According to a realist about propositional attitudes, belief states and other
attitude states exhibit a crucial combination of features: they have both causal
powers and semantic content or "aboutness". Cognitive psychology extends this
combination of features far beyond the realm of propositional attitudes.
So much for labouring the obvious point that cognition conceived as the
domain of cognitive psychology is much broader than cognition conceived as the
realm of beliefs and reasons.
The Credentials of Cognition
There are those who question the legitimacy of any kind of extension of semantic
content beyond the realm of propositional attitudes, which is the philosophical
ThinkingPersonsand CognitiveScience
41
home territory of "aboutness" or "intentionality". These sceptics seek to reject
the idea of a scientific psychology. They aim to impose a dichotomy: on the one
hand, science (with physics as the paradigm case) and, on the other hand, the socalled "folk psychology" of the non-scientific common-sense scheme of attribution of attitudes and explanation in terms of reasons. The sceptics bear the
onus of proof here; for the very existence of the discipline of cognitive psychology
confers prima facie legitimacy upon the extended notion of cognition.
If the friend of cognitive psychology sought to extend the domain of semantic
content by extending the space of reasons and justification, then the sceptic would
have a promising line of attack. On that reading, the attribution of tacit
knowledge of linguistic rules, for example, would involve two steps. First, in the
grip of the idea that there must be a step of justificatory reasoning preceding each
piece of linguistic understanding, the theorist attributes to each ordinary
language user a set of linguistic rules that are to be consulted in order to justify
actual linguistic practice. Then, second, confronted with the evident implausibility of such attribution of conscious knowledge of rules to anyone other than
linguists, the theorist says that, in the case of ordinary unreflective language
users, the knowledge and the consultation of rules is unconscious or tacit.
Conceived in this way, the position of the cognitive theorist really would
appear confused and, indeed, incoherent- involving as it does the totally
mysterious idea of unconscious justification. The root of the incoherence would
be located in the first of the two steps. For that step fails to heed a dominant
theme in Wittgenstein's philosophy; namely, that at a certain point justifications
give out.
However, cognitive science is not to be saddled with this incoherent position.
Cognitive science extends the domain of semantic content beyond the space of
reasons, rather than extending the space of reasons itself. The cognitive theorist is
not guilty of "giving a justification of our procedure where there is no such thing
as a justification" (Wittgenstein, 1976, III-74).
Within the broad class of cognitive states recognized by cognitive science there
will be propositional attitude states and there will be other psychological states
which also have semantic contents and figure in causal explanations. The first
subclass contains, centrally, beliefs, desires, and intentions. The second subclass
contains, for example, states that register information about the disparity
between two retinal images, or about the orthographic form of a word, and states
of tacit knowledge of linguistic rules.
Stich labels states in this second subclass as subdoxastic states. They are states
which "play a role in the proximate causal history of beliefs, though they are not
beliefs themselves" (1978, p. 499). In Chomsky's terminology, they are states of
(mere) cognizing.
Now it is certainly consistent to u r g e - against the sceptic- that the extended
cognitive domain is legitimate, while agreeing with the sceptic that there is
something special about the bearers of semantic content that fall within the
narrower realm of propositional attitudes. So it is open to us to stress the
importance of a distinction within the broad class of cognitive states recognized
by ~gnitive science: the distinction between beliefs and other attitude states on
the one hand, and subdoxastic states on the other.
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Martin Davi¢~
Connectionist models are being used in the study of many cognitive processes.
The patterns of activation in a connectionist network certainly exhibit the crucial
combination of features that is characteristic of all cognitive states. For patterns
of activation clearly have causal powers, and they also have semantic or
interpreted descriptions: patterns of activation are a network's way of registering
information about its environment. But what are the prospects for connectionism
in modelling the doxastic realm of thought and inference?
The answer to that question evidently depends upon the principle for
distinguishing between doxastic and subdoxastic states.
Consciousness and What It Is Like
It is a deeply appealing idea that, ff there is to be a principled distinction between
the realm of attitudes and the domain of mere information processing, then
consciousness should somehow mark the boundary. But I shall be arguing here
for a negative claim; namely, that the intuitive notion of consciousness cannot
bear the weight of a principled distinction between the doxastic and the
subdoxzstic (even if we ignore the possibility of unconscious beliefs).
One of the most basic thoughts about consciousness is that bats are conscious
while bricks are not. There is something that it is like to be a bat (Nagel, 1979),
but there is nothing that it is like to be a brick. This basic thought ties the notion of
consciousness to that of experience; and my negative claim is that this undifferentiated notion of conscious experience cannot furnish the principle that we
require.
We want to say that beliefs, for example, are conscious states. But there is
certainly more to conscious experience than propositional attitudes. Many
creatures enjoy conscious experience, but are not bearers of attitudes at all. As a
consequence, there is a sense in which a state that has a semantic content may be
accessible to consciousness while also being intuitively classified as subdoxastic
rather than doxasfie.
Suppose, for example, that certain low level states with semantic content prima facie examples of subdoxastic states - were to surface in conscious
awareness, as distinctive itches or fiches, perhaps. Then there would be
something that it was like to be in those states. But that empiric~ difference from
our actual situation would obviously not be enough to make those states into
beliefs.
It might be said that, in the imagined situation, the semantic content of the
state is in no way reflected by the character of the experience of being in the state.
The experience does not encode the content. But, while that is true, it is not
difficult to refine the example. Suppose that the semantic content of certain states
concerns the value of some parameter along a one-dimensional scale. And
suppose that the intensity of the itch or fiche varies with the value that the state
assigns to that parameter. Now what it is like to be in the state depends
systematically upon the semantic content of the state. But this still does not make
the state into a belief.
Thinking Persons and Cognitive Science
43
These hypothetical examples show that there can be aspects of experience
which make no difference to what a person taking his experience at face value
would believe about the world, even though the character of the experience does
systematically reflect information about the world. Those aspects of experience
amount to the surfacing in conscious awareness of states with semantic content,
but the experiences do not present those contents as potential contents of
judgement and belief.
The problem for the idea that consciousness marks the distinction between
doxastic and subdoxastic states is that semantic content plus consciousness (there
being something that it is like to be in the state) does not add up to the content of a
doxastic state.
We can gain a slightly different perspective on this problem if we consider a
distinction that is sometimes drawn within the character of perceptual experiences. The representational content of an experience is a matter of the way that
the experience presents the world as being; it is the way that a person taking the
experience at face value would thereby judge the world to be. This is to be
distinguished from the sensational or phenomenal properties of the experience
(Peacocke, 1983). One of the examples that can be used to illustrate the
representational versus sensational distinction is provided by monocular and
binocular viewing of the same scene. Monocular vision certainly does not present
the world as fiat; and provided enough depth cues are present, it is entirely
possible that the representational content of the two visual experiences should be
the same. Yet there is an intrinsic difference between the experiences: they have
different sensational properties. So sensational properties cannot be reduced to
representational ones.
But, nevertheless, the sensational differences that make no representational
difference may be underpinned by differences in the semantic contents of states
of visual processing. It does not seem entirely science fictional to suppose that the
sensational difference between the two experiences is to be explained in terms of
the presence or absence of information about binocular disparity in their causal
antecedents. Semantic content may surface in experience as a sensational rather
than a representational feature.
Given this terminology, we can say that the semantic content of a belief, or
other doxastic state, is representational content. Subdoxastic states have
semantic content, too. And the point that semantic content plus consciousness
does not add up to the content of a doxastic state emerges here as the claim that
semantic content can surface in experience without surfacing as representational
content.
Someone might reply in the following way, to this problem with the idea of
using consciousness to mark the distinction between doxastic and subdoxastic
states. We can allow that, in the imagined cases, a subdoxastic state with semantic
content is accessible to consciousness. But, even so, the content of the state is not
accessible to consciousness; and it is this that matters for a principled distinction
between beliefs and subdoxastic states.
This reply does not, strictly speaking, oppose my negative claim. For that claim
was concerned with the intuitive and undifferentiated notion of consciousness,
tied to the idea of there being something that it is like to be in a state. What the
44
Martin Davies
reply does amount to is a suggestion for refining the undifferentiated notion of
accessibility to consciousness; introducing the notion of accessibility of content to
consciousness.
If this suggestion is to furnish a principle of demarcation, then it will have to be
the case that the idea of accessibility of content is tolerably clear, and that it can
be employed in a non-question-begging way to distinguish doxastic from
subdoxastic states.
Let us ask first whether the idea is clear. What the examples that we have just
considered show is that accessibility of content would need to be sharply
distinguished from the mere systematic reflection of semantic content in aspects
of experience.
Accessibility of content would also need to be distinguished from the kind of
case where a person has beliefs about the semantic contents of his or her own
subdoxastic states. The fact that a theorist of vision, for example, may have
beliefs about the contents of the states implicated in the information processing
that is going on within him does not render those states any the less subdoxastic.
Nor does the possibility of a belief to the effect that the binocular disparity is suchand-such render doxastic the visual processing state of registering information
about disparity.
Accessibility to consciousness of the content of a state is not just the possibility
of beliefs about the content of a state, or beliefs with the same content as the
state. To be in a state with a semantic content is one thing; to have a belief about
that state is another.
For accessibility of the content of a state, we need to require that to be in that
state is ipso facto to have the content accessible. Then, borrowing from Fodor
(1983, p. 56), we could cash out accessibility as availability for exptieit verbal
report. The result would be the proposal that a state is doxastic, rather than
subdoxastic, if being in that state is ipso facto to have the semantic content of the
state available for verbal report.
However, just as it stands this gratuitously ties doxastic states too closely to
language. We do not want a principle of demarcation that simply legislates that
only a language user can think. The proposal is reasonably clear, and there is
something compelling about it. But the idea of actual verbal report seems to be an
inessential intrusion.
What is more fundamental than availability for report is availability for
thought. If we replace the inessential with the fundamental, then the proposal
comes to this. A state with semantic content is doxastic if being in that state is ipso
facto to have the content of the state available as a content of thought - of
propositional attitudes. A state is subdoxastic if being in the state is not ipsofacto
to have its semantic content available for thought.
What this says is true. But it is hardly a non-question-begging way of
distinguishing the realm of thought and inference from the subdoxastic domain.
For the proposal simply helps itself to the notion of thought.
Until we understand more fully what we are saying when we say that beliefs are
conscious states, we cannot make anything of the appealing idea that consciousness marks the boundary of the doxastic realm. It is time to turn elsewhere for a
principle of demarcation.
Thinking Persons and Cognitive Science
45
Conceptualized Content and the Structure of Thinking
It is a familiar neo-Fregean point that no one can have a belief with a particular
content - or entertain a thought with a particular content - without grasping the
constituent concepts of that content. For example, no one can believe, or even
entertain the hypothesis, that God is triune unless he knows what it is for
something to be triune. Someone who lacks that knowledge can merely believe
that the string of words "God is triune" expresses some true proposition or other,
not knowing which proposition it expresses.
However, there is no corresponding requirement relating to the semantic
contents of subdoxastic states. A person can certainly be in a state that registers
information about binocular disparity, for example, without that person having
the concept of binocular disparity. And, of course, ordinary language users who
are credited with tacit knowledge of linguistic rules, principles, or generalizations
are likely to have no grasp at all upon the technical concepts of linguistic theory.
They do not, for example, know what it is for one expression to c-command
another.
Consequently, the requirement that the semantic content of a state should be
conceptualized by the person whose state it is suggests itself as a foundation for
the distinction between propositional attitude states and other cognitive states.
The idea here is not simply that if a thinker happens to possess the concepts that
are involved in a content, then any state of the thinker which has that content is a
doxastic state. Of course, a person who enjoys binocular vision may also be a
theorist of vision, and so may indeed have the concept of binocular disparity. But
that does not make the low level state of registering disparity anything other than
subdoxastic. To be in the low level state whose semantic content concerns
binocular disparity is not ipso facto to have the content of that state available for
thought, and so does not itself require possession of the concept of binocular
disparity.
Strawson says (1959, p. 99) that "the idea of a predicate is correlative with that
of a range of distinguishable individuals of which the predicate can be significantly, though not necessarily truly, affirmed". This truth about predicates in
language has its echo for concepts in the realm of thought. If a thinker is to have
the concept of being F, then that thinker must know what it is for an object to be
F; and what this means is that the thinker must know what it would be for an
arbitrary object to be F.
If we put this truistic sounding doctrine about concepts together with the claim
that being in a doxastic state involves deploying concepts, then an important
consequence follows.
In order to entertain the thought that a particular object a is F, a thinker must
have the concept of being F. That is, the thinker must know what it is for an
arbitrary object to be F. So, if the thinker is able to think about some other object
b, then the thinker knows what it would be for that object b to be F. In short, if a
thinker is able to entertain the thought that a is F, and is able to think about b thinking perhaps that b is G - then the thinker has all the conceptual resources
that are required for also entertaining the thought that b is F(and the thought that
a is G).
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Martin Davies
This requirement upon thoughts is what Evans (1982, pp. 100-105) calls the
Generality Constraint. Semantic contents in general are not subject to this
constraint; but thoughts are subject to it because their semantic contents are
conceptualized by the person whose thoughts they are.
One immediate consequence of the Generality Constraint (perhaps not
properly distinguishable from the Generality Constraint itself) is that the class of
thought contents that are available to a given thinker exhibits a kind of closure
property. If the contents a is F and b is G are available, then so too are the
recombined contents a / s G and b / s F. Likewise, if the content a is R to b is
available, then so too is the content b is R to a.
It may be that, if we look at the semantic contents of some class of subdoxastic
cognitive states, then we shall find that those semantic contents also meet a
closure condition: the class of actual and potential semantic contents is closed
under recombination. But that possibility need not blur the distinction between
doxastic and subdoxastic states. Doxastic states have conceptualized contents,
are immediately answerable to the Generality Constraint, and so essentially meet
the closure condition. Subdoxastic states are not subject to the Generality
Constraint, and so, if they do meet the closure condition, then that is a merely
contingent fact about them. Their having the contents that they do is one thing;
their meeting the closure condition is another.
Suppose that we take conceptualization of semantic content as the principle for
distinguishing propositional attitudes from subdoxastic states. What, then, are
the prospects for connectionism in modelling the doxastic realm of thought and
inference?
Inference and Causal Systematicity
It is not easy to argue directly from the closure condition on thought contents to a
problem for the connectionist programme.
The friend of connectionism can point out, in the first instance, that it is
perfectly easy to devise little models that de facto meet the closure condition. A
system of four nodes - representing the four states of affairs a is F, b / s F, a is G,
b / s G - would serve.
The opponent can then object that this model is a mere toy; and he can claim
that to meet the closure condition in a realistic case would require some kind of
articulation in the states that bear semantic contents. He can claim, in particular,
that there would need to be constituents of the states- an a constituent, and an F
constituent, for example - and that this articulation into constituents would
amount to a syntax, which is just what connectionist models are supposed to do
without.
However, the friend of connectionism has a rejoinder. The opponent's
objection is essentially a "How else?" argument. Thus: "It is possible to meet the
closure condition on contents by using syntactically structured vehicles of
semantic content. How else could it be done?" But this style of argument is apt to
seem question-begging in the context of a proposed alternative style of vehicle for
semantic content.
Thinking Persons and CognitiveScience
47
The opponent can then regroup around the doctrine that thought contents are
essentially subject to the Generality Constraint, whereas connectionism makes
the satisfaction of the closure condition look like a mere contingency. But, here
too the friend of connectionism has a reply. For he can offer his opponent a
stipulation. Let it be stipulated that a semantic description of a network will not
amount to a description in terms of thought contents unless the closure condition
is met. That preserves an essential link between thoughts and closure, as the
opponent wanted. But it also acknowledges as a contingency the fact that any
given network has a degree of complexity that could warrant a doxastic
description.
There are further possible steps in this exchange, but we do not need to follow
them. For the closure condition on thought contents does not exhaust the
significance of the neo-Fregean idea of conceptualized content.
Part of what is involved in the idea of conceptualized content is that when a
thinker entertains the thought that a is F and also the thought that b is F, a
common piece of concept mastery is being deployed: both thoughts require
knowledge what it is for an object to be F.
This knowledge is implicated in a person's grasp of the inferential potential of
these two thoughts. For, to take a very basic case, suppose that part of what is
required for an object to be Fis that it should be H. Then a thinker will appreciate
that from a is F it follows that a is H, and from b is F it follows that b is H. The
thinker will be disposed to accept these two inferences; and, what is more, the
two inferential dispositions will be products of a common underlying capacity mastery of the concept of being F. What we arrive at is the idea of real causal
systematicity in inferential transitions.
Here is a very simple example of the way that this idea works. A thinker who
has the thought that Bruce is a bachelor appreciates that from this thought it
follows that Bruce is unmarried. He also appreciates that from the thought that
Nigel is a bachelor it follows that Nigel is unmarried. The thinker appreciates the
inferential potential of these two thoughts; and the inferential disposition
depends in each case upon the same general capacity- mastery of the concept of
being a bachelor.
In order to have either the thought that Bruce is a bachelor or the thought that
Nigel is a bachelor, the thinker must grasp the concept of being a bachelor.
Grasping the concept of being a bachelor is a matter of knowing what it is for an
object to be a bachelor; and that is matter of knowing inter alia that to be a
bachelor requires being unmarried. This single piece of knowledge is implicated
as a causal common factor in both of the inferential transitions that the thinker is
disposed to make.
Of course, this is a very simple example; very few concepts are easily definable
in the way that bachelor is. And even in this simple case, there will be many other
inferences that our thinker will draw concerning Bruce and Nigel. Often, the
conclusion about Bruce will be different from the conclusion about Nigel; and
even where the conclusions are similar there is no general guarantee of causal
common factors. All this is quite correct. But it does not undermine the idea that,
very often, part of what is involved in mastery of a concept, or of a family of
concepts, is commitment to a pattern of inference. When inferential transitions
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Martin Davies
that conform to that pattern are made, there is a commonality, not merely in our
descriptions of the transitions, but in their causal explanations as well.
It is this idea of causal systematicity of inferential transitions that is problematic
for connectionist models. A PDP system may certainly perform transitions which,
under a semantic description, conform to a certain pattern. But it is one of the
characteristic features of connectionist networks with distributed representation
that there is not a causal commonality in the way that the network performs the
various individual transitions conforming to the pattern.
In a localist connectionist network with a node for bachelor and a node for
unmarried, a connection between those nodes could function as a causal common
factor in transitions from patterns of activation with semantic contents . . . . . . /s a
bachelor to patterns with corresponding contents ~ / s
umarried. This,
incidentally, illustrates the important fact that strict causal systematicity does not
require explicitly represented rules.
But, with distributed representation what we expect to find is that there is no
common subpattern of the various patterns of activation that have the semantic
contents: Bruce is a bachelor, Nigel is a bachelor, and so on. Rather there will be
constituent subpatterns that exhibit both commonalities and differences. Consequently, there will not be a common pattern of weights on connections that is
implicated in all and only the bachelorto unmarried transitions. That is to say that
there will not be causal systematicity in these transitions.
In short, part of what is involved in the notion of conceptualized content is a
requirement of causal systematicity in inferential transitions. A PDP system may
perform the transitions; it may achieve the right input-output relation. But a
network, as such, will not model this causal systematicity. So, on the face of it, if
conceptualization of content provides the principle of distinction, then the
doxastic realm of thought and inference is problematic for connectionism.
Reconstructing the Mind
I began by defending the extension of the notions of cognition and semantic
content far beyond their philosophical home territory. I then sought a principle
for a distinction, within the broad class of cognitive states, between the doxastic
realm - the home territory of propositional attitude states - and the subdoxastie
domain. I argued that the intuitive notion of consciousness will not bear the
weight of such a distinction, and turned instead to the idea of conceptualization.
If the argument of the last section is right, then conceptual content brings with it a
kind of causal systematicity that is typically not exemplified by PDP systems.
This tells us that, if we attempt a cognitive scientific reconstruction of the
philosopher's notion of a thinking person, then a component in that reconstruction will be a system with an architecture more classical than connectionist. In
fact, there are plausible arguments (Fodor, 1987) linking systematicity of
cognitive processes with syntactic structure in representational states. So perhaps
we can say that something like the language of thought will be a component in the
construction of a thinker.
ThinkingPersons and CognitiveScience
49
There is a second Fodorian element that could plausibly contribute towards a
putative reconstruction: this is the idea of the modularity of mind (Fodor, 1983).
For it can hardly escape notice that the distinction between the realm of thoughts
with their conceptualized content, and the domain or domains of other cognitive
states is reminiscent of the distinction between the central cognitive system and
modules. What this suggests is that thoughts are content bearing states of a
central system, rather than of a module.
However, it is clear that a putative scientific reconstruction of the realm of
thoughts and concepts drawing on just these two elements would be only a partial
reconstruction. Being a content bearing state that is syntactically structured and
implicated in causally systematic processes, and being a state of a central system,
do not add up to being a thought. Less telegraphically, we can say this. There can
be a complex information processing system with the architecture of a central
system plus modules, and with its central system operating systematically over
syntactically structured states, but which is intuitively not a thinker, not a
deployer of concepts. (Many AI systems, such as planning and action systems,
illustrate this point.)
Many intuitions seem to converge here. For example, a thinker can be held
responsible for his beliefs; there are normative aspects to the doxastic realm.
Again, thought involves some kind of self-consciousness; there are reflective
aspects of the doxastic realm. It may be that cognitive science will make progress
with these normative and reflective aspects of thought. But the intuitions suggest
that there are features of our common-sense idea of the realm of judgement,
belief, and inference which may well not be fully captured in a scientific
psychological reconstruction. How should we respond to that suggestion?
Two extreme responses are evidently possible. One (the "British" response?)
is to conclude that cognitive science is best avoided. The idea here would be that,
since cognitive science does not reconstruct the philosopher's notion of a thinking
person, it is dehumanizing. (This might be regarded as a vindication of those
Wittgensteinian reservations about extending the notion of cognition.)
The opposite extreme (the "Australian" response?) is to credit philosophy with
something like superstitious hankering. The idea here would be that what science
does not reconstruct should be banished. Our conception of our own mentality
ought, in full seriousness, to be purged of whatever has no echo in a cognitive
psychological model.
But a choice between these extremes is not obligatory. It is surely allowable to
believe that the prospects for fruitful interdisciplinary liaison are not so dire.
Certainly, there is more to the study of the mind than computational psychology.
But still, representation and computation may well be the de facto underpinnings
of at least some psychological phenomena; and the empirical discipline of
cognitive psychology can and should inform philosophical theorizing.
We might even hope to advance beyond such a justified eclecticism. For if we
came to understand the relationships between the philosopher's and the psychologist's accounts of the mind - between folk psychology and its cognitive
psychological underpinnings - then we would have taken a step towards a
principled appreciatio n of the various levels of description of our mental life.
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Martin Davies
References
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