The Psychology Book (26 page)

1960s
Albert Bandura’s social

discipline in its own right.

reached the conclusion that they

learning theory is influenced

Skinner had once contemplated

must be utterly subjective, and

by radical behaviorism.

a career as an author, but he had

did not exist at all separately from

little time for the philosophical

the body. In Skinner’s opinion,

B.F. Skinner

Burrhus Frederic Skinner was

the rest of his life. He was

born in 1904 in Susquehanna,

diagnosed with leukemia in

Pennsylvania. He studied English

the 1980s, but continued to

at Hamilton College, New York,

work, finishing an article from

intending to be a writer, but soon

his final lecture on the day he

realized that the literary life was

died, August 18, 1990.

not for him. Influenced by the

works of Ivan Pavlov and John B.

Key works

Watson, he studied psychology at

Harvard, gaining his doctorate in

1938
The Behavior of Organisms:

1931 and becoming a junior fellow.

An Experimental Analysis

He moved to the University of

1948
Walden Two

Minnesota in 1936, and from

1953
Science and Human

1946 to 1947 ran the psychology

Behavior

department at Indiana University.

1957
Verbal Behavior

In 1948, Skinner returned to

1971
Beyond Freedom and

Harvard, where he remained for

Dignity

BEHAVIORISM 81

See also:
William James 38–45 ■ Ivan Pavlov 60–61 ■ John B. Watson 66–71 ■ Zing-Yang Kuo 75 ■

Joseph Wolpe 86–87 ■ Albert Bandura 286–91 ■ Noam Chomsky 294–97

press the bar accidentally, or

simply out of curiosity, and as a

consequence receive some food.

An action
,

Over time, the rat learned that food

such as a rat

appeared whenever the bar was

pressing a

pressed, and began to press it

button…

purposefully in order to be fed.

Comparing results from rats given

the “positive reinforcement” of food

for their bar-pressing behavior with

those that were not, or were

presented with food at different

rates, it became clear that when

food appeared as a consequence

…leading to an

…
has a

of the rat’s actions, this influenced

increased probability

consequence
,

its future behavior.

of that behavior

such as the

Skinner concluded that animals

and
encouraging a

delivery of food…

are conditioned by the responses

repeat
of the action.

they receive from their actions

and environment. As the rats

explored the world around them,

some of their actions had a positive

consequence (Skinner was careful

the way to carry out psychological

from the results of actions. As with

to avoid the word “reward” with its

research was through observable

so many great insights, this may

connotations of being given for

behavior, rather than through

appear to be self-evident, but it

“good” behavior), which in turn

unobservable thoughts.

marked a major turning point in

encouraged them to repeat that

Although a strict behaviorist

behaviorist psychology.

behavior. In Skinner’s terms,

from the outset of his career,

an “organism" operates on its

Skinner differed from earlier

Skinner boxes

environment, and encounters a ❯❯

behaviorists in his interpretation of

While working as a research fellow

conditioning, in particular, the

at Harvard, Skinner carried out a

principle of “classical conditioning”

series of experiments on rats, using

as described by Pavlov. While not

an invention that later became

disagreeing that a conditioned

known as a “Skinner box.” A rat

response could be elicited by

was placed in one of these boxes,

repeated training, Skinner felt that

which had a special bar fitted on

this was something of a special

the inside. Every time the rat

case, involving the deliberate,

pressed this bar, it was presented

artificial introduction of a

with a food pellet. The rate of

conditioning stimulus.

bar-pressing was automatically

To Skinner, it seemed that

recorded. Initially, the rat might

the consequences of an action

were more important in shaping

Skinner boxes
were one of many

behavior than any stimulus that

ingenious devices that the psychologist

had preceded or coincided with it.

created, giving him total control over

He concluded from his experiments

the environment of the animals whose

that behavior is primarily learned

behavior he was observing.

82 B.F. SKINNER

Positive reinforcement
can stimulate particular patterns

of behavior, as Skinner demonstrated by placing a rat in

one of his specially designed boxes, fitted with a lever or bar.

Pellets of food appeared every time the animal pressed the

bar, encouraging it to perform this action again and again.

stimulus (a food pellet), which

occurring, if the reinforcing

shock as “punishment,” a distinction

reinforces its operant behavior

stimulus was then stopped, there

that became increasingly important

(pressing on the bar). In order to

was a decrease in the likelihood of

as he examined the implications of

distinguish this from classical

that behavior occurring.

his research.

conditioning, he coined the term

Skinner continued making his

Negative reinforcement was not

“operant conditioning;” the major

experiments ever more varied and

a new concept in psychology. As

distinction being that operant

sophisticated, including changes of

early as 1890, William James had

conditioning depends not on a

schedule to establish whether the

written in
Principles of Psychology
:

preceding stimulus, but on what

rats could distinguish and respond

“Animals, for example, awaken in

follows as a consequence of a

to differences in the rate of delivery

a child the opposite impulses of

particular type of behavior. It is also

of food pellets. As he suspected,

fearing and fondling. But if a child,

different in that it represents

the rats adapted very quickly to

in his first attempts to pat a dog,

a two-way process, in which an

the new schedules.

gets snapped at or bitten, so that

action, or behavior, is operating

the impulse of fear is strongly

on the environment just as much

Negative reinforcement

aroused, it may be that for years to

as the environment is shaping

In later experiments, the floors of

come no dog will excite in him the

that behavior.

the Skinner boxes were each fitted

In the course of his experiments,

with an electric grid, which would

Skinner began to run short of food

give the rats an unpleasant shock

pellets, forcing him to reschedule

whenever they were activated. This

the rate at which they were being

allowed for the investigation of the

given to the rats. Some rats now

effect of negative reinforcement on

received a food pellet only after

behavior. Again, just as Skinner

they had pressed the bar a number

avoided the word “reward,” he was

of times repeatedly, either at fixed

careful not to describe the electric

intervals or randomly. The results of

this variation reinforced Skinner’s

Winning at gambling
often boosts

original findings, but they also led

the compulsion to try again, while

to a further discovery: that while

losing lessens it, just as changes in the

a reinforcing stimulus led to a

rate at which Skinner’s rats were fed

greater probability of a behavior

made them modify their behavior.

BEHAVIORISM 83

impulse to fondle again.” Skinner

was to provide the experimental

evidence for this idea.

Positive reinforcement

As expected, Skinner found that

whenever a behavior resulted in the

negative consequence of an electric

shock, there was a decrease in that

behavior. He went on to redesign

the Skinner boxes used in the

experiment, so that the rats inside

were able to switch off the

electrified grid by pressing a bar,

which provided a form of positive

reinforcement arising from the

removal of a negative stimulus. The

results that followed confirmed

Skinner’s theory—if a behavior

leads to the removal of a negative

likely to avoid doing so when adults

Skinner’s pigeon
experiments proved

stimulus, that behavior increases.

are around. The child may modify

that the positive reinforcement of being

However, the results also

his behavior, but only so far as it

fed on the achievement of a task helped

to speed up and reinforce the learning

revealed an interesting distinction

enables him to avoid punishment.

of new behavior patterns.

between behavior learned by

Skinner himself believed that

positive reinforcement and behavior

ultimately all forms of punishment

elicited by negative stimuli. The

were unsuitable for controlling

further in his article
The Selection

rats responded better and more

children’s behavior.

by Consequences,
written for the

quickly to the positive stimuli (as

journal
Science
in 1981.

well as the removal of negative

Genetic predisposition

In 1936, Skinner took up a post

stimuli), than when their behavior

The “shaping” of behavior by

at the University of Minnesota,