Transcript Week 11

Philosophy 4610
Philosophy of Mind
Week 11:
The Problem of Consciousness
AI and Consciousness:
Recap and Transition
 We considered the problem of whether a
computer could actually be intelligent or
thinking
 For many people, the biggest obstacle to
artificial intelligence is the question of
consciousness: could a computer actually
be conscious or (self)-aware?
 How could we tell if it were conscious?
The problem of consciousness
 In addition to all of our
behavior and functioning,
each of us is also
conscious – we have
experiences, sensations,
thoughts, etc. that we can
know from a first-person
perspective.
 The problem of explaining
how this is possible is one
of the most difficult in
philosophy today.
Defining Consciousness:
“What It’s Like”
 “But no matter how the forms may vary, the fact
that an organism has conscious experience at all
means, basically, that there is something it is like
to be that organism.” (p. 219)
 According to Nagel, we can say that X is
conscious if there is something that it’s like to be
X.
 Does this seem like an adequate definition?
What sorts of things satisfy the formula?
Defining Consciousness:
The “Subjective Quality of
Experience”
 According to Nagel, if there is something
that it is like to be me – if I am conscious –
then our experience has a subjective
quality (what it is like for me).
 Other philosophers have used the term
“qualia” (singular: quale) to refer to
subjective qualities of experience
 Example: redness of experienced red,
taste of pizza, sound of foghorn
Nagel and the problem of
explaining consciousness
 According to Nagel, the subjective
properties of experience, or qualia, will be
very difficult to explain from a scientific
point of view
 The reason is that scientific explanations
are objective (third-person) explanations.
But qualia or subjective qualities are
known only from a subjective (first-person)
point of view.
Scientific Explanation:
the ‘view from nowhere’
 Scientific explanations normally work by
abstracting from or eliminating our particular
points of view.
 The way we explain phenomena such as
lightning, or water, is to abstract from our own
particular point of view to gain access to what
we could see from any point of view.
 But in the case of consciousness, this is
impossible. For if we abstract from our own
point of view, we lose the phenomenon itself.
Example: What it’s like to be a bat
 There is something that
it’s like to be a bat
 But what it is like to be a
bat may be very difficult
to understand
 Usually, we understand
someone else’s
experience by analogy
with our own. But this is
very difficult in the case
of the bat.
Nagel: The difficulty of
understanding bat-experience
 I have said that the essence of the belief that bats
have experience is that there is something that it is
like to be a bat. Now we know that most bats …
perceive the external world primarily by means of
echolocation …Their brains are designed to
correlate the outgoing impulses with the
subsequent echoes, and the information thus
acquired enables bats to make precise
determinations of distance, size, shape, motion,
and texture … But bat sonar, though clearly a form
of perception, is not similar in its operation to any
sense that we possess, and there is no reason to
suppose that it is subjectively like anything we can
experience or imagine.” (p. 220).
The problem of consciousness
 According to Nagel, it is impossible or
almost impossible to give a physicalistic
explanation of the bat’s consciousness
 How might we try giving a physicalist
explanation? A functionalist explanation?
 What (if anything) would be left out of such
an explanation?
Nagel against physicalism
 According to Nagel, because of this
problem, there is at present no hope for a
physicalist explanation of consciousness.
 This doesn’t necessarily mean that
dualism is true – just that consciousness is
extremely difficult to explain in physicalist
terms.
Can we hope to explain
consciousness?
 “At the present time the status of
physicalism is similar to that which the
hypothesis that matter is energy would
have had if uttered by a pre-Socratic
philosopher. We do not have the
beginnings of a conception of how it might
be true.” (p. 224).
 Is the problem really as bad as Nagel
says? What might help?