PHIL 101
INSTRUCTOR: WILBURN
MODEL ANSWERS TO PUBLISHERS’ ESSAY TEST FOR CH. 2
1. Suppose that it is conceivable for a person to exist and not have a body. Does this prove
that the mind is separate from the body? Why or why not?
Even if this were conceivable (and there are reasons to suspect that it isn’t), it would still not
show that in the actual world, as it is governed by actual natural laws, disembodied personal
existence ever occurs.
2. Explain why the problem of other minds is a problem for Cartesian Dualism.
If the Cartesian dualist is right, then we can only have second-hand knowledge that others even
have minds, since all of our claims about others’ minds would have to be inferred from their
behavior.
3. Suppose that Duncan McDougall is correct that people lose ¾ to 1 ½ ounces at the
moment of death. Would this lend credibility to the theory of Cartesian Dualism? Why or
why not?
Presumably it wouldn’t, since, on Descartes’ account, minds are immaterial and thus devoid of
weight.
4. Suppose that, as Descartes claimed, the mind is indivisible. Would that lend credibility to
the theory of Cartesian Dualism? Why or why not?
Presumably not, since it might still very well be the case that minds are capacities of bodies in
much the way that voices are capacities of vocal chords. Just as voices are not divisible, neither
would minds be. But that would not mean that neither (minds nor voices) could exist in the
absence of those objects of which they are capacities (brains/bodies nor vocal chords).
5. Is Cartesian Dualism consistent with modern science? Why or why not?
At present, it looks as though Cartesian Dualism is not comfortably compatible with modern
science. Modern science implies the causal closure of the physical, according to which every
physical event has a physical cause. We might try to get around this by construing minds as
causally inert. But it is difficult to believe that our thoughts and feelings could have no causal
influence on our behavior (or vice versa).
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6. Explain the implications of Searle's brain replacement thought experiment.
Searle imagines that each and every neuron in one’s brain is replaced by a computer chip that
serves precisely the same switching function as the neuron it replaces. Searle asks us to imagine
what might happen as a result of this. The first possibility is that one remains completely
unchanged. The second possibility is that one becomes a zombie (behaving normally but without
mental states). A third possibility is that one remains conscious but paralyzed.
The imaginability of the second possibility shows that logical behaviorism must be false. The
imaginability of the third possibility shows that both logical behaviorism and identity theory
must be false.
7. What does the perfect pretender thought experiment show about behavioral
dispositions?
It shows that having such and such behavioral dispositions cannot be sufficient for having such
and such mental states.
8. Explain how Nagel's bat thought experiment attempts to undermine identity theory.
It purports to show that it is not possible to know everything there is to know about the mind by
knowing everything there is to know about the brain. No purely physical description of a
conscious organism can capture the “subjective nature” of that organism’s experience. Thus,
identity theory must be mistaken.
9. Explain the significance of the fact that brain states are knowable by empirical
investigation but mental states are not.
This fact seems to suggest that the essential characteristics of mental phenomena cannot be
entirely captured in the terms of physical science. This suggests that identity theory must be
false.
10. What does Lewis's pained Martian thought experiment show about the identity theory?
This seems to show that two creatures could be in the same mental state despite being in very
different material states (i.e., one has a recognizable brain and the other does not).
11. Explain the absent qualia objection.
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This is the objection to functionalism that one creature could conceivably be the same functional
state as a second creature, even thought the first has conscious experience and the second does
not.
12. Explain the inverted spectrum problem.
This is a graphic demonstration of the absent qualia objection. We are asked to imagine a being
which is just like us except that its visible spectrum is inverted 180 degrees. Since it will acquire
color language and beliefs exactly as we do (i.e., calling the same things “red” that we call
“red”), it will be in a state of seeing a certain shade of blue when and only when we see a certain
shade of red. Functionalism tells us that these two states are identical because they play the same
causal roles relative to inputs and outputs (including other mental states). But, intuitively we
want to say that seeing blue just feels vastly different from seeing red.
13. What does Searle's Chinese room thought experiment show?
The Chinese room allegedly does for intentional states what the inverted spectrum thought
experiment shows for phenomenal states. It has us envision a situation in which a human being
serves essentially the same function as the CPU of a digital computer which is running a
simulation program for understanding Chinese. And yet, we intuitively want to say that neither
this person nor the system of which she is a part actually understands Chinese.
14. Explain why intentionality creates a problem for functionalism.
Intentional states are cognitive states of belief, desire, etc. which are of or about something. If
functionalism were true, then being in an intentional state I would be identical with being in a
functional state F. But, as the Chinese Room thought experiment reminds us, we can easily
imagine F occurring with I occurring.
15. Is being in a certain functional state a necessary or sufficient condition for being in a
certain mental state? Why or why not?
Mental states are intentional (thought-like) and phenomenal (feeling-like). The Chinese Room
thought experiment seems to show that being in a certain functional state cannot be sufficient for
being in a certain intentional state. The Inverted Spectrum thought experiment seems to show
that being in a certain functional state cannot be sufficient for being in a certain phenomenal
state. The corresponding necessity claims are a different matter, since it may very well be the
case that the right kind of program has to be run in the right kind of hardware for either feeling or
thought to occur.
16. What does Searle's thought experiment about Chevrolet station wagons show?
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It shows that we cannot conclude that an item is unreal just in virtue of the fact that no explicit
mention of it is made in our fundamental theory of nature
17. What is the point of Jackson's thought experiment about the color-challenged scientist?
This thought experiment allegedly shows that not everything there is to be said about reality can
be said in the language of physical science (since this would leave qualia out of account).
18. Is it possible to provide a complete account of the world in purely physical terms? Why
or why not?
Again, it doesn’t seem so, since qualia cannot be characterized in terms of a completely physical
vocabulary.
19. Is folk psychology an inadequate psychological theory? Why or why not?
Folk theory cannot explain many things (e.g., sleep, learning, memory). But, if folk theory is
intended only to explain the waking actions of normal adults, then it would seem to be
completely adequate.
20. Is eliminative materialism a good theory of mind? Why or why not?
It would seem that it isn’t because of the inability of purely materialist theories to explain the
likes of experiential qualia.
21. What does it mean to say that intentionality is a primitive property?
A primitive property is a property that cannot be analyzed in terms of one or more other, more
basic, properties.
22. Explain the concept of downward causation and why it implies that human behavior
cannot be explained in purely materialist terms.
Downward causation would occur if emergent higher-level properties of systems somehow
imposed changes in the subvening lower-level properties of the components of these systems.
To be a complete materialist requires that one accept the conservation of mass/energy. On the
face of it, however, it would seem that downward causation would violate this principle, as it
would require that energy be introduced back into lower levels of reality from which it did not
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emerge in the first place. Thus, it would seem that a commitment to downward causation is
incompatible with a commitment to full-blooded physicalism.
23. How does contemporary property dualism differ from substance dualism?
Substance dualism requires the existence on distinctly mental states (or properties) and
substances. Property dualism requires only the existence of distinctly non-physical states (or
properties).
24. How does the existence of downward causation help solve the problem of free will?
It would explain how our choices and decisions could influence our physical behavior.
25. Why does Searle's view of mental and physical properties seem to be a form of
epiphenomenalism?
Searle wants to liken the phenomenal and intentional states and properties of folk psychology to
the non-quantum states and properties of higher-level physical objects (e.g., split-level ranch
houses and Chevrolet station wagons). The problem is that in the case of these latter examples,
higher-level properties (of macroscopic objects) fail to influence lower-level properties (of
fundamental particles). So, if Searle is committed to these analogies, he is left unable to explain
how states of one’s mind can influence states of one’s body.
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