Transcript The Mind-Body Identity Theory

Functionalism and the MindBody Problem
Michael Lacewing
[email protected]
© Michael Lacewing
Metaphysics of mind
• Substance: needs no other thing to exist
• Dualism: there are two sorts of substance,
mind (or soul) and matter
– Mental properties are properties of a mental
substance
• Materialism: there is just one sort of thing,
matter
– Mental properties are properties of a material
substance
Mental properties
• Substances can have
different sorts of
properties
• Property dualism:
mental properties are
not physical properties
Hmm…
• Type identity theory:
mental properties are
physical properties
– Thinking a thought is
exactly the same thing
as certain neurones
firing
Reduction
• Ontological reduction: the things in
one domain (e.g. mental things) are
identical with some of the things in
another domain.
• Reduction: this makes the ‘reduced’
domain more intelligible
Multiple realizability
• Mental properties cannot
be identical to physical
properties because the
same mental property can
be ‘realized by’ different
physical properties, e.g.
the brain states that relate
to pain are different in
different species, but pain
is the same mental state.
Functionalism
• The property ‘having the function x’ can be
realized by many different things, e.g. being
a mousetrap, being a poison
• Mental properties/states are functional
properties/states - if a physical state plays a
certain causal-functional role, then it is a
mental state
• Token identity: each mental state is nothing
more than a physical state (playing a certain
function)
Consciousness
• Can consciousness be reduced to
functions? The issue of ‘qualia’
– Inverted spectrum
– Absent qualia: the Chinese mind
– Feelings aren’t functions
• Replies
– could a state play exactly the functional
role of pain and not feel like pain?
– Feelings are not just functions, but
depend on physiological properties as
well
Consciousness
• Appealing to physiology undermines
multiple realizability.
• The point is: feelings can’t be reduced
to anything else - property dualism
Searle’s Chinese Room
• Functionalism can’t
distinguish a real mind
from a simulation
• The Chinese room:
input, output, rulebook
• Reply: wrong causalfunctional roles
identified;
understanding is
nothing more that
interaction, but more
complex than this
Mental causation
• Causation requires things to
‘happen’.
• ‘Things happening’ are
events. A cause and its
effect are both events,
changes at a time (or over
time) in the properties of
objects.
• Like picking up the remote
control
Properties and causes
• Events cause their effects
in virtue of certain
properties and not others.
• Is it because of its physical
properties or because of
its mental properties that
a mental event causes its
effects?
• The mental (functional)
property is explained in
terms of the causal powers
of the physical properties
Picturing the problem
Mental event, e.g. pain
=
Physical event, e.g. in brain

But physical property
explains effect
 ‘Ow!’