E.J. Lowe - There are no easy problem of consciounsness.pdf

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There Are No Easy Problems of Consciousness 1
E. J. Lowe
Department of Philosophy, University of Durham, Durham, UK
This paper challenges David Chalmers’ proposed division of the problems of conscious­
ness into the ‘easy’ ones and the ‘hard’ one, the former allegedly being susceptible to
explanation in terms of computational or neural mechanisms and the latter supposedly
turning on the fact that experiential ‘qualia’ resist any sort of functional definition. Such
a division, it is argued, rests upon a misrepresention of the nature of human cognition
and experience and their intimate interrelationship, thereby neglecting a vitally impor­
tant insight of Kant. From a Kantian perspective, our capacity for conceptual thought is
so inextricably bound up with our capacity for phenomenal consciousness that it is an
illusion to imagine that there are any ‘easy’ problems of consciousness, resolvable within
the computational or neural paradigms.
David Chalmers is to be commended for challenging the complacent assumptions of
reductive physicalism regarding the tractability of the problems of consciousness, but
he concedes too much to such physicalists in allowing that some, at least, of these
problems — the ‘easy’ ones — will fall prey to their favoured methods. 2 I do not con­
sider that there are any ‘easy’ problems of consciousness, and consider that Chalmers’
division of the problems into ‘easy’ ones and the ‘hard’ one betrays an inadequate con­
ception of conscious thought and experience — a conception which plays into the
hands of physicalists by suggesting that the only problem with functionalism is its
apparent inability to say anything about ‘qualia’ . 3
At the beginning of his paper, Chalmers lists some of the problems of consciousness
which he considers to be ‘easy’, in the sense that these are the ones which, in his view,
‘seem directly susceptible to the standard methods of cognitive science, whereby a
phenomenon is explained in terms of computational or neural mechanisms’ (p. 200).
These problems include: the ability to discriminate, categorize and react to environ­
mental stimuli; the integration of information by a cognitive system; the reportability
of mental states; and the deliberate control of behaviour. Chalmers remarks that, ‘All
1 Originally published in Journal of Consciousness Studies 2 (3), 1995, pp. 266–271. Copyright ©
Imprint Academic 2005. Reproduced with permission.
2 See Chalmers (1995); all page references are to this paper.
3 Much of what I have to say about consciousness, thought and experience in this paper is
developed at much greater length in Lowe (1996) and, in an earlier version, in Lowe (1992).
A NTI M ATTERS 2 (1) 2008
of these phenomena are associated with the notion of consciousness,’ and confidently
asserts that, ‘All of them are straightforwardly vulnerable to explanation in terms of
computational or neural mechanisms’ (p. 201). But it needs to be pointed out at once
that the terms employed in describing these problems — terms like ‘discrimination’,
‘information’, ‘report’ and ‘control’ — are extremely slippery, and that we use them
both in a ‘high level’ way to describe the conscious, intelligent activity of genuinely
thoughtful creatures like ourselves and also in a ‘low level’ way (which may in fact be
no more than a metaphorical way) to describe the programmed behaviour of mindless
machines and various lowly forms of life. For example, we may speak of a thermostat
as ‘discriminating’ ambient temperatures and as ‘controlling’ a switch, or of a com­
puter as storing ‘information’ and ‘reporting’ on the contents of its ‘memory’. But
there is no reason whatever to believe that the activities thus described really have
much in common with those activities of thoughtful human beings which we would
customarily describe in these same terms. To suppose otherwise is to fall victim to the
so-called pathetic fallacy — the fallacy of ascribing thought and feeling to mindless
objects on account of superficial likenesses between their behaviour or appearance
and our own. Now, it is true enough that the activities of thermostats and computers
which we describe in such terms can indeed be explained in the ways Chalmers sug­
gests, but it is far from evident that those of human beings can. Indeed, I shall try to
make it evident in what follows that the latter activities can certainly not be explained
in these ways, and that the reason for this has to do with the nature of human con­
sciousness and its relation to our capacities for thought, understanding and concept-
As a preliminary to tackling this task, I want to say something more about Chalmers’
notions of experience and consciousness, which I find seriously inadequate. As regards
the notion of experience , it seems to me that he distorts this notion by focusing exclu­
sively upon the sensuous , or phenomenal , or qualitative character of experience (the
‘what it is like’ aspect of experience, to use Thomas Nagel’s well-worn phrase). And
this distortion serves, in my view, to obscure the intimate relation between experience
and thought. Some experiences — pains provide a possible example — are indeed
almost purely sensational in character, but the sort of experiences which are central to
our cognitive capacities — namely, perceptual experiences — are certainly not. Percep­
tual experiences — such as, for example, a visual experience of seeing a red book lying
on top of a brown table — possess not only qualitative or phenomenal characteristics
but also , most importantly, intentional or representational content. Not only is it ‘like
something’ to enjoy such an experience, in which the phenomenal character of sensed
colours impresses itself upon our awareness, but also such an experience represents —
or, better, presents — our immediate physical environment as being some way (in this
case, as containing a red book on top of a brown table). Moreover, and quite crucially,
the intentional content of such an experience stands in an especially intimate relation
to its qualitative or phenomenal character: the two aspects of the experience are not
simply independent of one another.
I want to say that the intentional content of a perceptual experience is, in a certain
sense, grounded in its phenomenal character, but that the grounding relation here is a
complicated one, which arises at least in part through the subject’s individual history
of perceptual learning. One of the most important things we learn through perception
is what various sorts of physical object look like (or otherwise ‘appear’ to other sense
modalities — what they sound like , and feel like , for instance). And how objects look to us
is, at least in part, a matter of how they affect the phenomenal or qualitative character
of our visual experience. (The same applies, mutatis mutandis , with regard to the other
sense modalities.) The importance of all this lies in the fact that how we conceive of
physical objects is inextricably bound up with how they appear to us in perception —
how they look , sound , feel and so forth. Thus, although conscious thought is not, of
course, the same thing as perceptual experience, the conceptual content of thought is
intimately related to the content, both phenomenal and intentional, of perceptual
experience. Thoughts differ from perceptual experiences in possessing only intentional ,
and not sensuous content; yet, even so, the intentional content of our thought depends
inescapably, by way of its conceptual structure, upon our capacity to enjoy perceptual
experiences with sensuous or phenomenal characteristics. And, at the same time, our
perceptual experiences possess intentional content — often, the very same content as
may be possessed by our thoughts — because we are able to bring concepts to bear
upon the deliverances of our sense organs and so clothe our perceptual sensations
with representational properties.
All this has been said before, of course — and no doubt much better than I have been
able to — by Immanuel Kant, and is encapsulated in his famous dictum that ‘Thoughts
without [sensible] content are empty, [sensible] intuitions without concepts are
blind’ (1933, p. 93). But the upshot is that it is quite erroneous to suppose that we can
ascribe genuine thoughts, with conceptually articulated structure, to creatures or
machines lacking altogether the capacity to enjoy conscious experiences with phe­
nomenal or qualitative character. Whatever a computer can do by way of information
processing, storage and retrieval is not by any means to be confused with what a
thinking human being does who reasons, remembers and recalls. And here I note a
particularly serious inadequacy in the (essentially Shannonian) notion of information
which Chalmers deploys in attempting to characterize aspects of human cognition.
This notion of information is appropriate enough for describing the activities of com­
puting machines, but is wholly inappropriate for characterizing the cognitive states —
beliefs, thoughts and judgements — of human beings. And the reason, once again, has
to do with conceptual content . An informational state in Chalmers’ sense is not, essen­
tially, a state possessing conceptually articulated content; but the beliefs, thoughts and
judgements of human beings most certainly do possess such content essentially. A sim­
ple, if somewhat timeworn, example will serve to bring out this distinction. Consider
the pattern of rings exposed by a horizontal cut through a tree’s trunk: such a ring pat­
tern is, in the sense of ‘information’ deployed by Chalmers, an informational state of the
tree — it carries ‘information’ about the tree’s age, amongst other things. Clearly,
though, it is not a state with conceptual content: it would be ludicrous to suggest that
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the ring pattern somehow embodies the concepts of number and time (concepts which
are themselves involved in the analysis of the concept of a tree’s age). By contrast, one
cannot properly ascribe to a person a belief that a certain tree is so-and-so many years
old without simultaneously ascribing to that person concepts of number and time. And,
once again, I would appeal to the Kantian principle that our conceptual capacities —
even those relating to such relatively abstract concepts as those of number and time —
are intimately related to our capacities for perceptual experience, in order to explain
what the relevant difference between a human being and a tree is in this regard. That a
tree can merely carry (Shannonian) ‘information’ about its age, whereas a human
being can believe that, or think that, it has a certain age is intimately related to the fact
that human beings can, whereas trees cannot, enjoy conscious perceptual experiences
with phenomenal character.
So far I have criticized Chalmers’ notions of experience and information , but there is a
related criticism I have to make which goes to the heart of his attempted distinction
between the ‘easy’ problems of consciousness and the ‘hard’ problem. This concerns
his terminological proposal regarding the use of the words ‘consciousness’ and ‘aware­
ness’. Chalmers suggests that we ‘reserve the term “consciousness” for the phenomena
of experience, using the less loaded term “awareness” for the more straightforward
phenomena described earlier’ (p. 201). But given that I dispute Chalmers’ claim that
the latter phenomena are indeed ‘more straightforward’ (in the sense of being
amenable to computational or neural explanation), I cannot acquiesce in his termino­
logical proposal. To do so would be, implicitly, to concede far too much to reductive
physicalism and at the same time would be to gainsay all I have just said concerning
the intimate relationship between phenomenal consciousness and the intelligent
thought and activity of human beings. In Chalmers’ proposed sense of ‘awareness’, it
seems fair to say, there could be nothing in principle wrong in speaking of a computer,
or even a thermostat, as being ‘aware’ — but then to suggest that human beings are only
‘aware’ in this attenuated sense is completely to misrepresent the capacities involved
in our being ‘aware’ of our selves and of our own thoughts and experiences.
My foregoing criticisms of Chalmers bear directly upon section III of his paper, in
which he attempts to explain why the ‘easy’ problems are easy and the ‘hard’ problem
hard. Here he asserts that ‘The easy problems are easy precisely because they concern
the explanation of cognitive abilities and functions [and] to explain a cognitive function,
we need only specify a mechanism that can perform the function’ (p. 202). He gives the
following example, amongst others: ‘To explain reportability . . . is just to explain how
a system could perform the function of producing reports on internal states’ ( ibid .).
But, of course, I must immediately protest that if by ‘producing a report on an internal
state’ Chalmers just means generating a second-order informational state (in the Shan­
nonian sense of ‘information’), then although this is something which can indeed be
perfectly well explained in a mechanistic way, it is not the sort of thing that needs to be
explained when we are talking about the ability of human subjects to express in words
their knowledge of the contents of their own thoughts and experiences — for such an
ability demands the possession of genuine concepts, not only concepts of the things
those thoughts and experiences are about but also the very concepts of thought and
experience themselves. And the truth is that we have not the slightest reason to believe
that a ‘mechanistic’ explanation is available, even in principle, for the capacity of crea­
tures like ourselves to deploy the concepts of thought and experience and to ascribe
the possession of such concepts to ourselves. Only by trading upon a thoroughly jejune
sense of ‘reportability’ can Chalmers make out even the appearance of a case for saying
that such a capacity, as exercised by human beings, is ‘easy’ to explain as being a ‘func­
tion’ performed by a computational or neural mechanism.
The key point here is that a ‘function’, in Chalmers’ sense, is specified in terms of cer­
tain behaviour which a system subserving that function produces. (As Chalmers himself
puts it, ‘Here “function” is . . . used . . . in the . . . sense of any causal role in the produc­
tion of behavior that a system might perform’ (p. 202 f).) But then everything turns on
how we characterize the ‘behaviour’ in question. In the example just discussed, the
‘behaviour’ in question was described by Chalmers as that of ‘producing reports on
internal states’. But only if such ‘behaviour’ is interpreted in a narrowly physicalistic
way — for example, in terms of the generation of a second-order (Shannonian) infor­
mational state — is a ‘mechanistic’ explanation of the corresponding ‘function’ going
to be straightforwardly available. If, by contrast, we understand ‘producing reports on
internal states’ to embrace such genuinely intelligent, thoughtful activities as a human
being’s using language to express its knowledge of the contents of its own thoughts
and experiences, then there is not the slightest reason to suppose that a mechanistic
explanation for this capacity is possible. Mechanistically characterized ‘behaviour’ is,
quite unsurprizingly, amenable to mechanistic explanation, and this is what underlies
Chalmers’ own perception that ‘In a way, the point is trivial’ (p. 202) — the ‘point’ being
that you can always explain the performance of a function by ‘specifying a mechanism
that performs the function’ ( ibid .). Chalmers’ problem is that he entirely begs the real
question at issue in supposing that the sort of performance we have to do with in cases
of thoughtful human activity is something that can be characterized in a mechanistic
way and which, consequently, a ‘mechanism’ can uncontroversially be supposed capa­
ble of engaging in.
Because Chalmers misconstrues what he sees as being the ‘easy’ problems of con­
sciousness, he also misrepresents what he calls the ‘hard’ problem. According to
Chalmers, the ‘hard’ problem is this: ‘Why doesn’t all this information-processing go
on “in the dark”, free of any inner feel?’ (p. 203). Believing as he does that human
thought and cognition in general are just a matter of ‘information-processing’, of a sort
which could in principle go on in a mindless computer, he is left with the idea that all
that is really distinctive about consciousness is its qualitative or phenomenal aspects
(the ‘what it is like’, or ‘inner feel’). And then it begins to look like a strange mystery or
quirk of evolution that creatures like us should possess this sort of consciousness in
addition to all our capacities for thought and understanding — these capacities being,
for Chalmers, simply capacities for certain sorts of information-processing and storage.
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