Transcript Behaviorism

Behaviorism
Methodological Behaviorism
Classical Conditioning
While investigating the digestion
of dogs, Ivan Pavlov (1849-1936)
observed that the dogs in his
laboratory would salivate when
they saw the people who brought
their food.
Classical Conditioning
Pavlov theorized that he could
make the dogs salivate to any
thing or event, if he had first
presented it with food.
Animal Behavior vs. Psychology
Pavlov won a Nobel prize in
physiology and medicine for this
work.
He was a physiologist, not a
psychologist.
At the time, psychology was
mostly the study of conscious
experience.
Associationism
Pavlov’s research suggested
something like this:
Animal behavior is controlled by
the environment. Animals are
born behaving in certain natural
way, and learned behavior is
through a process of association.
Introspectionism
At the time, psychology was focused on individuals reporting
details of their conscious experience. To make this rigorous, there
was a heavy focus on expertise:
• Wundt required his subjects to perform 10,000 introspective
observations before they were considered sufficiently trained.
• Titchener wrote 1000 page training manual for experimental
introspection.
Training was supposed to provide subjects with:
• An increased capacity for attention
• An ability to properly distinguish such facets of experience as
‘tonal intensity’ and ‘tonal clearness’
• An ability to avoid confusions such as ‘stimulus error’ – the
description of the object experienced as opposed to the
experience itself.
Famously, however, none of the psychological labs got the same
results! For example, they couldn’t agree whether one could introspect
imageless thoughts.
John B. Watson
• American psychologist
• 1878-1958
• Progenitor of methodological
behaviorism
Psychology as the Behaviorist Views It
In “Psychology as the Behaviorist Views It,” Watson characterizes
psychology as:
• ‘purely objective’
• ‘a branch of natural science’
• Concerned with ‘prediction and control of behavior’
• NOT concerned with conscious states
• Opposed to introspection
• Recognizing no difference between human and animal
Watson vs. Introspectionism
“If you fail to reproduce my
findings, it is not due to some
fault in your apparatus or in the
control of your stimulus, but it is
due to the fact that your
introspection is untrained… If you
can't observe 3-9 states of
clearness in attention, your
introspection is poor.” (pg. 6).
Behaviorism
The conclusion Watson draws is: we must get rid of all references to
consciousness. We shouldn’t use terms like ‘mental state’,
‘consciousness’, ‘mental image’, or even ‘mind’. These aren’t scientific
terms.
The vocabulary of psychology should only involve terms for behavior,
stimulus, and so on.
“[P]sychology as a behaviorist views it is a purely objective
experimental branch of natural science. Its theoretical goal is …
prediction and control”
The Pervasive Positivism
This movement was part of the positivist zeitgeist of the time. Things
that aren’t publicly verifiable– like mental states and their qualities–
were not suitable objects of scientific study.
B. F. Skinner
• American psychologist
• 1904-1990
• Verbal Behavior
• Beyond Freedom & Dignity
• Walden Two
Huckle Buckle Beanstalk
• Player 1 hides an object
• Player 2 moves in random directions and Player 1 says “hotter” if
Player 2 is closer to the object and “colder” if Player 2 moves farther
from the object.
• Eventually, Player 2 finds the object
Generate and Filter
Operant Conditioning
Skinner introduced a variety of conditioning explicitly modeled on
Darwin’s ideas.
Classical conditioning (Pavlov) sets up an association between two
external stimuli.
Operant conditioning sets up an association between a behavior and a
subsequent reward/punishment.
Skinner Box
The Law of Effect
Rewarded behaviors increase in frequency, punished ones decrease.
Cf. the law of natural selection: fitter phenotypes increase in frequency,
less fit ones decrease.
Skinner’s Radicalism
Watson was primarily concerned
with methodology – we shouldn’t
talk about internal mental states
because they cannot be
objectively studied.
B. F. Skinner
Skinner believed that we
shouldn’t talk about internal
mental states because the entirety
of a person’s behavior can be
explained in terms of the stimuli
in their environment – internal
mental states don’t have an
explanatory role.
Are Mental States Suspect?
We can’t see or hear or feel or taste mental states. The methodological
behaviorists assumed they were therefore not objective or scientific.
BUT, lots of unobservable things are completely objective and
scientific: electrons, dinosaurs, the earth’s core.
Against Methodological
Behaviorism
Chomsky vs. Skinner Part 1
Noam Chomsky wrote an
influential critique of Skinner’s
views.
In particular, he argued that
stimuli didn’t control our behavior.
From one stimulus, lots of
behaviors were possible.
The Rembrandt
• “Dutch.”
• “Wow!”
• “It’s a Rembrandt.”
• “This old stuff really bores me.”
• “Let’s steal it!”
• “Can you believe the city paid
$32 million USD for that?”
Chomsky vs. Skinner Part 2
Chomsky thought the environment didn’t directly control your
behavior– your mental states mattered too.
In particular, he thought that we had innate (in-born) knowledge that
determined our behavior.
Universal Grammar
Chomsky thought that in order to
learn a language, you had to know
in advance that certain thing were
impossible, because you were
very unlikely to get evidence that
agreed or disagreed with them.
Philosophical Behaviorism
Philosophical Behaviorism
Perhaps it’s possible to have our cake and eat it too.
According to the philosophical behaviorists, mental states exist, and
they explain our behavior.
But mental states aren’t private things: they are dispositions to behave
in certain ways.
The Problem of Other Minds
If this is true, then it might help solve a longstanding problem in
philosophy: how do we know that other people have mental states?
Here’s the solution: mental states = behavioral dispositions. We
observe the dispositions, and thus observe the mental states.
Wittgensteinian Motivations
According to Wittgenstein, the
meaning of a word is related to
our use of that word:
“The meaning of the word ‘length’
is learnt among other things, by
learning what it is to determine
length.” PI, sec. 199
Wittgensteinian Motivations
So by analogy, to learn the
meaning of ‘X has a toothache’
would be to learn how to
determine that someone had a
toothache, which we do by
observing their words and deeds.
Dispositions
Dispositions
• The vase is fragile: a dispositional property.
• To be fragile is to be such that if you are hit or dropped, then you
break.
• When the vase breaks there are two explanatorily relevant features:
1. its being hit or dropped and 2. its being fragile
A Dispositional Account of Mental States
Normally, we say that we are disposed to behave in certain ways when
we are in pain.
MSs Don’t Cause Dispositions
Ravenscroft makes clear that according to behaviorism, pain doesn’t
cause me to say “ouch” when I’m hit.
Pain = me saying “ouch” when I’m hit.
Not about Finding Out
It’s normally true that I find out about other people’s mental states by
observing their behavior.
But normally we think we observe their behavior.
The philosophical behaviorist thinks we observe their mental states!
1. Physical Events Cause MSs
Ravenscroft says this is a plus for behaviorism: supposedly states of the
world cause MSs. E.g. standing on a tack causes pain.
But is this true? Does standing on a tack cause me to have the
disposition that when I stand on a tack, I say “ouch”? Usually I have
that disposition prior to standing on tacks.
2. Some MSs Cause Actions
The glass broke when I dropped it because it was fragile. (Is this just
Moliere again?)
5. MSs Represent Things
“The English word ‘dog’ expresses the property of being a dog… This
semantical fact about English reduces to a certain fact about the
behavioral dispositions of English speakers; viz, that their verbal
response ‘dog’ is… under the control of dogs.” – Fodor, “A Theory of
Content I,” describing Skinner’s view.
MSs Correlated with Brain States
Analogy: fragility correlated with molecular structure. (Dispositional
and categorical properties.)
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Argument for Phil. Behaviorism
People’s behavior in certain circumstances is evidence for what mental
states they have or lack. (E.g. wanting or not wanting something.)
If their mental states = behavior in certain circumstances, then it’s
obvious why that is.
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Argument for Phil. Behaviorism
(Obviously this argument isn’t conclusive. No one thinks electrons are
dispositions to bond in certain circumstances.)
Empiricist Criterion of Cognitive Significance
According to the logical positivists, in order for a sentence to have
cognitive significance (to be meaningful), it had to have verification
conditions.
(‘Verification’ is a Latinate English word < ‘veri-’ true + ‘facere’ to make.
Verification conditions are conditions under which the truth of a
statement can be conclusively established.)
Empiricist Criterion of Cognitive Significance
In fact, the positivists maintained that the meaning of a sentence was
its verification conditions. So a sentence with no verification
conditions– where no experience can establish its truth– is
meaningless.
Truth vs. Verification
Many philosophers (even today) have identified the meaning of a
sentence with its truth conditions. These are the circumstances in
which the sentence would be true. But the positivists went farther–
they held that the meaning of a sentence was its verification
conditions– the circumstances in which we would know the sentence
was true.
The Elimination of Metaphysics
This was part of a radical philosophical agenda, which included “the
elimination of metaphysics.” The idea was to view many philosophical
problems of the past (and also many religious claims) as meaningless
disputes that could simply be ignored.
The Elimination of Metaphysics
Example: In a religion where God is beyond human experience, the
positivists would say that “God exists” is neither true nor false but
meaningless, since no experience could verify it.
Kant, Hegel, and Heidegger were also big targets for the positivists.
Example Hegel quote: “But the other side of its Becoming, History, is a
conscious, self-meditating process — Spirit emptied out into Time.”
Positivism for Behaviorism
Since the way we discover whether people are in pain, believe that it’s
raining, want coffee, etc. is by observing their behavior in certain
circumstances, “X wants coffee” means “X drinks coffee when…”
Against Philosophical
Behaviorism
Logical Relations
From:
1. If Joe fails the final exam, he will fail the course.
2. If Joe fails the course, he will not graduate.
It follows logically that:
3. If Joe fails the final exam, he will not graduate.
Logical Relations
If you believe:
1. If Joe fails the final exam, he will fail the course.
2. If Joe fails the course, he will not graduate.
These beliefs can cause you to also believe:
3. If Joe fails the final exam, he will not graduate.
Rationality
It’s not clear how behaviorism can explain the rationality of mental
processes.
We can have dispositions to behave in all sorts of ways that aren’t
rational. (Outside control doesn’t respect rationality.)
Consciousness
Paralyzation and surgery. (Cf. Super-stoics.)
Consciousness
Pretending to feel pain.
Behavior Depends on LOTS of MSs