PP111 Lecture 8 Notes
Minds and Machines
Mind Brain Identity Theory: A Reductionist Form of Materialism
• Reductionist Materialism: Every Kind of mental state is (=) a kind of physical
state of the brain
o Water is H 0 2
o Lightening is an atmospheric electrical discharge
o A belief that it is raining is a particular electrochemical state of the
o (Generalization of the mind and brain states)
• Reductionist Materialism accepts generalizations about mindbrain
Some Consequences of a Reductionist Form of Materialism
• If two people have all the same mental states, then they will have all the same
• If two people have none of the same brain states, then they have none of the same
• Can we judge whether the physical shape and connected mental states means that
you are thinking of the same?
Troubles for Reductionist Materialism
• If feeling amused just is an increase in electrochemical activity in the inferior
temporal gyrus, then anything lacking an inferior temporal gyrus would be
incapable of feeling amused
1. Objection 1: Reductionist Materialism is Chauvinistic:
a. Could nonhuman animals have minds?
b. Could physiologically diverse aliens have minds?
c. Could future supercomputers have minds?
• Reductive Materialism says “No”
• BUT: We can’t know the answer to these questions without empirical
investigation; to decide without checking is merely “chauvinism”
• We should not be able to meet with aliens and predict in advance
• Is there any good reason for why aliens cannot love?
o Assuming humans can love: reductionists believe that only being with
the make up of humans can experience love
2. Objection 2: Multiple Realizability (The plastic of the Brain)
a. Broca’s Area responsible for speech production and articulation
• The same mental state can be physically constituted (“ realized”) in the brain in
more than one way. • So, something that does not have the same kind of brain we have, or whose brain
is not constituted in the same way ours is, can still have other kinds of physical
states that qualify as beliefs, desires, etc…
Functionalist Theory of Mind
• A nonreductionist form of the materialist theory of mind that allows for the same
types of mental states to have different physical constitutions (ie. different
• When we talk about our mental states, we are actually talking about our brain
states, but in a vocabulary that describes their functional roles.
• Functional Roles (functional identities):
o Professors (tall, short, male, female)
o Coffee tables (different materials)
o Bait (different materials)
o Beliefs (carbon based brain states, silicon based brain states)
Some Important Consequences of the Functionalist Theory of Mind
• Whether something has a mind has nothing to do with its particular physical
composition, but only with the functions (jobs, tasks) its part’s perform.
• Physically different kinds of things can think, feel, etc., so long as they do what
we do when we think, feel, etc
o Ie. Mental equivalence to us not= Physical equivalence to us
but, Mental equivalence to us = Functional equivalence to us
• Functionalism is then, a form of nonreductionist materialism. It remains a form
of materialism, since mental states remain physical states, but it is nonreductionist
because no generalizations can