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Course: Wireless Philosophy > Unit 7
Lesson 8: Eliminative materialismEliminative materialism
In this Wireless Philosophy video, we ask whether our familiar “folk psychological” ways of explaining and predicting human behavior could and should eventually be replaced by the more scientifically-grounded accounts being developed by neuroscientists. If neuroscience ends up giving us a more precise and reliable understanding of human behavior, will we still have any reason to believe in things like desires, beliefs, emotions, or any of the other mental states posited by folk psychology?
View our Neuroscience and Philosophy learning module and other videos in this series here: https://www.wi-phi.com. Created by Gaurav Vazirani.
Video transcript
In this WiPhi video we’re going to ask: will neuroscience replace folk psychology? Why should you believe in electrons? No one has ever seen one —
not even with an electron microscope. But according to excellent
scientific theories, electrons exist. These theories are extremely successful, practically powerful, and accepted
by experts in every scientific discipline. We know electrons exist, because they play an essential role
in many of our best scientific theories. Such things are called
theoretical entities. A theoretical entity is something
that we are confident is real, but only because it has to be real in order
for a theory we believe in to be true. Well, this might sound
like a strange question, but what about beliefs? What evidence do we have that
there even are such things as “beliefs”? Why believe in beliefs? Or
desires, or hopes, or fears, or any of the other mental
states we regularly attribute to others and ourselves? One idea is that beliefs
are theoretical entities too. “Folk psychology” refers
to our capacity to explain and predict other
people’s behavior. Many philosophers think of folk
psychology as a kind of “theory” that says things like, “When someone believes
there is a tiger in the vicinity, and they fear tigers,
they will attempt to flee”. Our understanding of beliefs,
fears, and other mental states stems from the role they play in folk
psychological explanations of behavior. After all, what is a belief? Well, it’s not easy to give a definition. But we all understand
how beliefs function. Consider two people
leaving for work. Each has to walk to the bus stop;
neither wants to get wet. One brings an umbrella,
while the other doesn’t. What explains this difference? Folk psychology
suggests several answers. The simplest is:
one of them believes it might rain, while the other one doesn’t. This explanation also enables us
to make accurate predictions. For example, which one
will be surprised if it rains? If it’s a theory, folk psychology
is an extremely useful one! We literally couldn’t survive without it. So, if we can be confident
that electrons exist because of the success of
the theories that posit them, we can be confident that beliefs exist because of t success of
the theory that posits them! However, this line of thought
leads to a troubling question. Electrons are posited by many
of our best scientific theories. But is folk psychology our
best theory of human behavior? Is it even a good one? A theory’s practical utility is
not the only thing that matters. Why does the sun set? Here’s one theory: the sun is a cowardly god
who is frightened by humans, and spends every day traveling
across the sky trying to escape our gaze. This theory predicts with perfect
accuracy that the sun will set tomorrow. However, we have no
reason to believe that it’s true. We have a much better theory
to explain the sunset — namely, that the earth rotates
on its axis every 24 hours, and hence the sun disappears
from view from each part of the planet once every 24 hours. What if there were a
theory of human behavior that didn’t involve
beliefs, desires, and so on? And what if this theory were
even better than folk psychology? Good as it is, folk
psychology is hardly fool-proof! We’re often wrong about why someone did
what they did, or what they will do next. Some philosophers think that
neuroscience will eventually give us a much better theory of human
behavior than folk psychology. But if that happens, would we still have any basis for
thinking there are such things as beliefs, desires, and the other mental
states posited by folk psychology? Old biological theories posited the existence of
“vital spirits” to explain life. Contemporary biochemistry
has no need for vital spirits, as it can explain life processes in
terms of general chemical principles. Since it’s a superior theory in many ways, we no longer have any basis for
positing the existence of vital spirits. Eliminative materialists think neuroscience will prove superior
to folk psychology in just the same way that biochemistry is
superior to vitalism. Unlike folk psychology, it’s unified with chemistry, physics,
and the rest of modern science; it’s capable of precise
experimental testing; it’s developing slowly and methodically on the basis of a foundation
of very well confirmed findings, fostered by a global
community of experts. And unlike folk psychology, neuroscience doesn’t
posit the existence of beliefs, desires, or any other
ordinary mental state. It deals in brains, chemistry,
physics, and mathematics. If neuroscience gives us a better
theory for understanding human behavior than folk psychology does, would we still have any
reason to believe in beliefs? What do you think?