Feist−Feist: Theories of
Personality, Seventh
EditionV. Learning Theories 15. Skinner: Behavioral
Analysis(^464) © The McGraw−Hill
Companies, 2009
“it is all a matter of natural selection, since operant conditioning is an evolved
process, of which cultural practices are special applications” (p. 55).
Natural Selection
Human personality is the product of a long evolutionary history. As individuals, our
behavior is determined by genetic composition and especially by our personal histo-
ries of reinforcement. As a species, however, we are shaped by the contingencies of
survival. Natural selection plays an important part in human personality (Skinner,
1974, 1987a, 1990a).
Individual behavior that is reinforcing tends to be repeated; that which is not
tends to drop out. Similarly, those behaviors that, throughout history, were beneficial
to the species tended to survive, whereas those that were only idiosyncratically rein-
forcing tended to drop out. For example, natural selection has favored those individ-
uals whose pupils of their eyes dilated and contracted with changes in lighting. Their
superior ability to see during both daylight and nighttime enabled them to avoid life-
threatening dangers and to survive to the age of reproduction. Similarly, infants
whose heads turned in the direction of a gentle stroke on the cheek were able to
suckle, thereby increasing their chances of survival and the likelihood that this root-
ing characteristic would be passed on to their offspring. These are but two examples
of several reflexes that characterize the human infant today. Some, such as the pupil-
lary reflex, continue to have survival value, whereas others, like the rooting reflex,
are of diminishing benefit.
The contingencies of reinforcement and the contingencies of survival interact,
and some behaviors that are individually reinforcing also contribute to the survival
of the species. For example, sexual behavior is generally reinforcing to an individ-
ual, but it also has natural selection value because those individuals who were most
strongly aroused by sexual stimulation were also the ones most likely to produce off-
spring capable of similar patterns of behavior.
Not every remnant of natural selection continues to have survival value. In hu-
mans’ early history, overeating was adaptive because it allowed people to survive
during those times when food was less plentiful. Now, in societies where food is con-
tinuously available, obesity has become a health problem, and overeating has lost its
survival value.
Although natural selection helped shape some human behavior, it is probably
responsible for only a small number of people’s actions. Skinner (1989a) claimed
that the contingencies of reinforcement, especially those that have shaped human
culture, account for most of human behavior.
We can trace a small part of human behavior... to natural selection and the
evolution of the species, but the greater part of human behavior must be traced
to contingencies of reinforcement, especially to the very complex social
contingencies we call cultures. Only when we take those histories into account
can we explain why people behave as they do. (p. 18)
Cultural Evolution
In his later years, Skinner (1987a, 1989a) elaborated more fully on the importance
of culture in shaping human personality. Selectionis responsible for those cultural
practices that have survived, just as selection plays a key role in humans’ evolution-
458 Part V Learning Theories