Transcript Philosophy 4610 - Villanova University

Philosophy 4610
Philosophy of Mind
Week 4: Objections to Behaviorism
The Identity Theory
Carnap:
“Psychology in Physical Language”
• Carnap (1891-1970) was
•
a dedicated physicalist
who believed that
everything in the world is
physical
He argues that we can
take any sentence that
seems to describe a
mental experience or
event and rewrite it in a
completely physical
language.
Carnap and Logical Behaviorism
• Logical Behaviorism is the view that
when we talk about “the mind,” we are
really just talking about the behavior of the
body (and hence about something that we
can describe completely in physical terms.
• For instance, we might translate, “Abner is
angry” as: “Abner’s face is red; his fist is
shaking; and he is yelling.”
• How might we translate other “mentalistic”
sentences?
Logical Behaviorism: objections
• Logical behaviorism seems plausible for
mental states that are always closely
connected to behavior. But what about
my mental state of thinking about the
weekend or dreaming of a better future?
• It seems clear that sometimes our
behavior does not manifest our true
mental states: for instance we may be
acting, or covering up how we truly feel.
Logical behaviorism: dispositions
• According to Carnap, at least some mental
•
states are actually not actual behaviors but
rather dispositions to behave. To say that I am
thinking about the future is just to say that I
would say “yes” if I were asked whether I was
thinking about the future.
Just as a glass can be “fragile” even if it is not
actually breaking, I can be in a certain mental
state even if I am not actually exhibiting it right
now.
Dualism and logical behaviorism:
Summary
• Descartes thought that mind and body were two
•
•
completely separate substances, interacting
through the pineal gland.
Ryle criticizes this view for failing to explain our
knowledge of others’ minds and for giving an
implausible picture of human beings as “ghosts
in machines.”
Carnap’s physicalist picture – logical behaviorism
– identifies the mind with outer, public behavior
and with dispositions to behave.
Putnam: “Brains and Behavior”
• Hilary Putnam (1926-)
is also a physicalist,
but he criticized
logical behaviorism
and contributed to
the development of
an alternative theory.
Problems with Logical Behaviorism?
• If logical behaviorism is true, then every
sentence about a mental event must be
translatable into a sentence about behavior
that means the same thing.
• For instance, every time we say, “Mr. A is
in pain,” this must be translatable into
some sentence about Mr. A’s actual or
possible behavior.
• But Putnam thinks this is not plausible.
Super-Spartans and X-Worlders
• To show this, Putnam
•
imagines a race of “SuperSpartans” who are culturally
trained never to show any
signs of pain.
We can even imagine a race
of “X-Worlders” who not
only never show pain, but
they never even talk about
pain.
Super-Spartans and X-Worlders
• For the X-worlders, it does not even make sense
•
to think that there is any translation from “Mr. X
has pain” to a sentence about pain-behavior.
Nevertheless it still makes sense to think they
may have pain:
“What is true by hypothesis is that we couldn’t
distinguish X-worlders from people who really
didn’t know what pain is on the basis of overt
behavior alone. But that still leaves many other
ways in which we might determine what is going
on ‘inside’ the X-worlders – in both the figurative
and literal sense of ‘inside’. For example, we
might examine their brains.” (p. 51)
Smart and the Identity Theory
• J. J. C. Smart (1920-) gave
the classic formulation of the
Identity Theory
• According to the Identity
Theory, the mind just is the
brain. When we talk about
mental events such as pains,
feelings, and sensations, we
are just talking about states
and processes in the physical
brain.
Smart and the Identity Theory
• Like Carnap and Putnam, Smart is also a
physicalist:
– “It seems to me that science is increasingly
giving us a viewpoint whereby organisms are
able to be seen as physico-chemical
mechanisms: it seems that even the behavior
of man himself will one day be explicable in
mechanistic terms. There does seem to be, so
far as science is concerned, nothing in the
world but increasingly complex arrangements
of physical constituents.”
Smart and the Identity Theory
• But unlike logical behaviorists, Smart thinks that
all mental events – such as after-images – can be
identified with states of the brain:
– “Maybe this is because I have not thought it out
sufficiently, but it does seem to me as though, when a
person says ‘I have an after-image,’ he is making a
genuine report, and that when he says ‘I have a pain,’
he is doing more than ‘replace pain-behavior,’ and that
‘this more’ is not just to say that he is in distress. I am
not so sure, however, that to admit this is to admit that
there are nonphysical correlates of brain processes.
Why should not sensations just be brain processes of a
certain sort?” (pp. 61-62)
Objections to the Identity Theory
• According to the Identity Theory, the
mental state of having a toothache or an
after-image is the same thing as a certain
brain state, X. But we can know about
toothaches and after-images without
knowing anything about brain states.
Response
• According to Smart, the identity between
an after-image and brain-state X is
something we do not necessarily know
about before we do science. It’s like the
identity between water and H20. We can
know all about water without knowing
anything about H20, but that doesn’t mean
they’re not identical. We just have to do
some science to find out that they are.