"Opinion says hot and cold, but the reality is atoms and empty space."
Democritus
Jackson’s Black and White Mary (1) case illustrates
an argument that our first-person experience of qualia provides knowledge not
accessible through third-person means. This argument seems suspicious: if
‘knowledge’, by definition, needs to be grasped in third-person terms, it is
inconceivable how an exclusively first-person experience may give us knowledge.
Harman (92) develops complementarity of subjective and objective aspects within his
functionalism of concepts. This notion needs to be extended to epistemic complementarity.
I refer to Classical German Philosophy, Phenomenology and Marxism which have developed a complementary
approach crucial in the reductionist anti-reductionist controversy in philosophy of mind.
I. The Knowledge Argument
As Jackson (86) emphasizes in his polemics with Churchland (85) the main point of the
case of Black and White Mary is not that Mary cannot ‘imagine’ what it is like
to sense red but that "she would not know" (2) how
red things look. I accept this argument, but not the next step. Jackson argues: "But
if physicalism is true she would know; and no great powers of imagination would be called
for." (3)
There are two versions of physicalism: the first, against which Jackson has something
to say, maintains that every instance of knowledge can be couched in third-person
language. (4) But the assumption that physical information
is solely what "you can tell" is not a necessary condition of physicalism.
Jackson's criticism does not reach another version of physicalism which assumes that
everything is physical but says nothing about it being ‘describable’.
Physicalism of the second kind presupposes that "there is no difference without
physical difference" (5) but it does not imply that
every physical difference can be described in language.
That the knowledge argument works against the first but not against the second form of
physicalism can be seen in Jeckson's reply to one of Churchland’s (6)
objections:
(1)' Mary (before her release) knows everything [physical] there is to know about other
people.
(2)' Mary (before her release) does not know everything there is to know about other
people (because she learns something about them on her release).
Therefore,
(3)' There are truths about other people (and herself) which escape the physical story.
(7)
The conclusion (3)' follows from premisses (1)' and (2)' only if the first kind of
physicalism is assumed; otherwise either premise (1)’ is unsatisfied, or conclusion
(3)’ goes too far. Before we examine these possibilities it is worth pointing out
that in most of the literature premise (2)’ is criticized; Mary is said to learn
nothing. But (2)’ seems undeniable since she does learn a new capacity, which is also
Nemirow’s and Lewis’(90) point.
The First Criticism
Nemirow argues (8) that knowing 'what it is like' is not
propositional knowledge but a linguistically inexpressible ability like wiggling ones ears
or riding a bicycle; it is not knowledge. This objection to the knowledge argument is
supposed to dismiss Jackson's Knowledge Argument. Obvioulsy, this objection does not hit
Nagel's argument which does not take first-preson experience to be justifiable by
third-person knowledge.
Nemirow's argument is tacitly based on a tertium non datur distinction between
"knowledge that may be summarized propositionally" and "abilities"
which are supposed not to be knowledge and therefore be somehow irrelevant for questions
of epistemology, like qualia. As the second type of physicalism demonstrates this
dichotomy is untenable. ‘Knowledge how’ is a sort of knowledge (the only kind of
intersubjectively verifiable knowledge that Mary did not have); whether it can be
"summarized propositionally" is irrelevant for the present argument. Mary did
not know "everything there is to know about other people" and consequently
premise (1)’ is unsatisfied whereas premise (2)’ is satisfied.
We may use the notion of knowledge* in a sense in which whatever is know* is sayable
and in this sense Mary learns* nothing exactly because of the reasons Lewis and Nemirow
present (her new ability is non-verbal). But this argument is implausible partly because
of the unusual notion of ‘knowledge*’. Furthermore, Jackson would have one more
move in this game (had he not defined his 'knowledge' as "whatever can be
told"). He could argue that, although it is not knowledge* that Mary acquires on
seeing her first red object, what she gets is a basis for such knowledge*. Lewis says this
in his formulation of ‘ability hypothesis’ (Lewis 90); unfortunately Jackson
does not join him on this.
I conclude that the knowledge argument can be ammended along the lines suggested by
Lewis as a "basis for knowledge argument". In this form it may be defensible.
The Second Criticism
The criticism questioning (1)’ has been adopted by Harman (90): Mary did not know
everything physical that there is to know about other people since she did not know
"how the concept R [red] functions with respect to the perception of things that are
red". (9) Harman’s objection presumes that we
should give a functionalist account of the content of concepts as well as of mental
states.
Harman contrasts this kind of functionalism with Lewis’ functionalism which does
not include a functionalist account of concepts. He also questions the ability of the
latter to answer Jackson’s criticism "since it is clearly false to say that the
person blind from birth does not lack any information". (10)
Consequently, Harman (90) approves Jackson's argument against traditional functionalism
but constructs a broader 'functionalism of concepts' supposed to sustain Jackson's
argument. (11) Truths about other people which escape
third-person description do not necessarily "escape the physical story" if by
'physical story' one understands physicalism (and not a story about physicalism). Harman's
argument shows that Jackson's argument does not reach physicalism of concepts.
The Turing Test for Perceptive Robots
The fact that Jackson’s criticism does not succeed with physicalists of the second
kind can be shown if we consider an imitation game similar to Turing’s classical test
(12) but differing from it in one important respect. As in
the test’s original version, we try to find out which of the participants is a human
and which an artificial intelligence. The difference is that the participants in the
original Turing Test are computers judged for their ability to engage in a conversation
whereas our game-partners are judged solely on the basis of their ability to discriminate
qualia. We may call this test the Turing Test for Perceptive Robots.
In Turing’s article there is a remark about the possibility of constructing a
machine able "to enjoy strawberries and cream". He refers to an attempt to
construct one as "idiotic" but far from an impossibility. I am not particular
about strawberries and cream, but there is nothing idiotic in constructing thousands of
different machines detecting waves within visible and audible spectra or chemical
substances one might taste, i.e. detecting qualia, which are used for different purposes
including in the military and space programs. (These machines usually also detect impulses
outside our possible sensory experience, but this is not our concern.)
Let me define a game some of these robots could play, called "The Black and White
Mary Game". Some robots are trained exactly the way Jackson’s Mary has been:
A). Although they are able in principle to detect ‘visual’ inputs of the kind
Mary would call ‘red’, they haven’t been actually exposed to this sort of
experience in the past (like Mary hasn’t seen anything red).
B). They have also extensive information about colors formulated in terms of physics
(the way Mary has) i.e. in a third-person language.
At some point a red ripe tomato is demonstrated to the robot V (the way it was shown to
Mary in Jackson's example).
What happens next?
Mary and robot V behave in exactly the same manner. Upon receiving the impulses (which,
in Mary's case, we interpret as qualia) the robot "learns something about the world
and visual experience of it" — to repeat Jackson’s
sentence about Mary’s experience. (13) There is no way
to sort out which reactions are produced by a robot (V) and which by a human (Mary). (14)
This is a fatal blow to the Knowledge Argument.
Any Further Results?
The Turing Test for Perceptive Robots does not prove the reductionist conclusion that
Mary and computer V do not differ. This conclusion would imply that there are only two
choices:
1. A behaviorist conclusion: Assuming that Mary has qualia, and given the above test,
we need to grant that the robot also has them. In functional terms we need to say that
computer 'enjoys seeing red' exactly the way Mary does just because its behaviour is
indistinguishable from Mary's.
2. The common sense conclusion that neither the robot nor Mary has qualia.
Although Mary's and computer's behavior is not distinguishable by an external observer,
the results say nothing about qualia understood in first-person Nagelian terms.
The intuitive appeal of Mary’s case that the robot’s case lacks does not come
from any form of the Knowledge Argument. It originates from an aspect of the Black and
White Mary’s case not covered by this argument, from the 'what it is like' problem.
Computers do not have the first-person experience of qualia. Mary leaving her bedroom is
supposed to become acquainted with them in a way specific to conscious subjects
but this fact does not manifest itself functionally in any special way. The crux of
Jackson's thesis is that they do, but the robot example shows in what way he is mistaken.
Schoemaker seems right arguing (in reference to the inverted qualia argument) that it
gives us good reasons not to adopt functionalist criteria of verification. (15)
The same is true about qualia in general. Functional differences are not enough to account
for differences with regard to qualia.
To conclude this section, the Turing’s Test for Robots proves that the information
argument does not determine solutions about qualia in any way. There is no peculiarity of
Mary’s behaviour that a robot could not exhibit: the information Mary did not have is
exactly the information robot V also lacked. The test shows that the Knowledge Argument
against physicalism falls to pieces unless Jackson chooses to endorse an unattractive
thesis that robots' behavior also disproves physicalism (that robots have an irreducible
mental insight).
II. A Second Try
Now I shall take as given the following facts: Mary's and the computer's cognitive
position is the same and their success in solving the correlation problem depends on their
information-processing abilities, not on any abilities specific to humans that robots
would a priori lack. The intuitiveness of the Knowledge Argument comes from some
introspective, first-person experience that we expect Mary, but not a robot, to have.
First-Person Qualia
In his "Epiphenomenal Qualia" Jackson emphasizes differences between his
'knowledge argument' and Nagel's question 'what it is like' in the following way: "I
was not complaining that we weren't finding out what it is like to be Fred. I was
complaining that there is something about his experience, a property of it, of
which we were left ignorant". (16)
But Jackson is right only in a sense in which 'physical information' is defined as
whatever can be told or given as a third person knowledge (17) — we have rejected this claim in a
previous section. Computer V, while playing "The Black and White Mary Game",
acquires nothing else than the "physical information" Jackson is refering to.
So, we are left ignorant about two different things concerning Mary's experience. One of
them is information common to Fred, Mary and to the robot V; we have no reason not to call
this sort of information physical. There is also a second aspect of Mary's experience, the
one Nagel focuses on — information of the kind "what it is
like". I don't expect a computer to have this strictly first-person experience, and
only this experience constitutes what seems 'not physical' in Mary's case.
Nagel makes it clear that it is impossible to analyze the first-person experience
"in terms of any explanatory system of functional states, or intentional states,
since those could be ascribed to robots or automata that behaved like people though they
experienced nothing." (18) The first person statements
are based on an immediate experience (or on a hermeneutics) of qualia, and not on proof of
any kind.
This conclusion leaves us with all the numerous and well discussed problems that
Nagel's 'what is it like' thesis produced. But Nagel's position has evolved substantially
since 1974 when his "What is it like to be a bat" was first published. In his
later and subtler approach Nagel tries to "juxtapose the internal and external or
subjective and objective views" (19) emphasizing that
neither of these perspectives is clearly superior. In particular the first person
perspective cannot be reduced to objective, third-person knowledge since there are things
which "can only be understood from the inside". (20)
Points of view, characterised as "irreducible features of reality", provide the
first-person perspective. This perspective cannot be stated in terms of external truth
conditions. (21)
Jackson criticizes Nagel's position as "weak from a polemical point of view".
(22) But since his alternative seems to fail I doubt if any
polemically stronger argument in favor of strictly subjective qualities can be developed.
Unlike Jackson, Nagel does not have illusions that there is a way of providing the
evidence of first-person experience on the basis of third-person abilities, dispositions
or behavior.
For Those Who Remain Faithful
In the remaining part of this paper I shall limit myself to following Terry Horgan's
approach and to: "direct the subsequent discussion at those who consider it obvious,
as I do, that the qualitative aspects of mentality are not definable functionally." (23)
Belief the qualitative aspects of mentality are not definable functionally lies behind
Harman's functionalism of concepts which accepts qualia as complementary to the functional
aspects. Harman adopts Dilthey's notion (he calls it Das Verstehen) which refers to
the understanding non-reducible to the method of physical science in studying the mind. Das
Verstehen refers to the irreducibly first-person experience necessary for
understanding certain claims e.g. "Pain!" As Harman put it, obviously following
Nagel: "You can know everything objective there is to know about a person without
knowing what it is like to be that person". (24)
According to Harman's the language has its objective (or intersubjective) and
subjective aspects. We are interested not only in transmitting objective, externally
verifiable information, but we also care about other people's first-person experiences (it
includes Das Verstehen). Hence, there are two different kinds of stories you can
tell about an event like pain:
1). An objective story (in a third-person language): that it is caused by nerve
irritations, causes distress, and motivates one to eliminate the irritation. 2). A
subjective story (in a first-person language): what it is like to feel pain.
Harman's radical claim is that one may understand the objective story without
understanding what it is like to be in pain, although these two different stories may
satisfy the same criteria of confirmation. Lacking acquaintance with qualia one fails to understand
something, which is different from not being able to confirm something. (25)
A full understanding of the objective truth conditions of the word "red" does
not give a full understanding of this word since a part of such understanding is knowing
what red things look like. Mary's lack of subjective understanding how red things look
means that she does not have a full understanding of something objective, namely, the
proposition that something is red.
Harman targets an important misconception about our language as lacking interest in
subjectivity. His criticism of positivist reductionism is based on an appreciation of two
different facts: the physical facts about experience (e.g. physiology of seeing red) and
an understanding of what it is like to see something red. (26)
This leads him to a complementary structure of argument which require both: scientific
third-person knowledge and Das Verstehen.
The issue of complementarity of our language is an aspect of a broader complementarity
between the subjective and objective viewpoints. The issue, introduced to the contmeporary
American philosophy by Nagel, has a longer history. Diltay's notion comes from Kant's
First Critique. It was further developed in Fichte's introductions to philosophy of
knowledge. Trough Husserl the issue became crucial to phenomenology and through Marx
it reached Marxism as dialectics of subjectivity and objectivity. (27)
In this paper I can not present these arguments I discuss these issues elsewhere (Boltuc
87, 88, 90).
My point is only to show that qualia present a problem for American philosophy: they
are hard to defend whereas qualia reductionism is intuitively implausible. Kantian
tradition, which might have been overemphasized in recent American ethical theory, remains
neglected in metaphysics while it, as well as its later European developments, may be able
to provided further grounds for complementarity of the subjective (28)
and objective view-points.
One final remark, complementarity of the subjective and objective epistemic starting
points has been discussed in Anglo-American philosophy, but these works have not been
influential. It was presented in the clearest form by Gordon Globus, who later retracted
these views for what seem to have been insufficient reasons. It was also discussed by
Albert Shalom, probably thanks to his leanings towards phenomenological tradition.
Finally, C. O. Evans in Britain endorsed something like complementarity while defending
epistemic non-reducibility of consciousness. Unfortunately none of these arguments has
been presented resolutely enough. Even Nagel's (79) persuasive argument on the subjective
and objective perspectives stops short of endorsing an idea that epistemological
complementarity is here to stay. This is why Harman's article, although it endorses
complementarity only in a limited domain, is an important breakthrough in analytical
philosophy.
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