People have wondered for a long time how their personalities and behaviors are formed. It is not easy to explain why one person is intelligent and another is not,or why one is cooperative and another is competitive.
Social scientists are,of course,extremely interested in these types of questions. （61） They want to explain why we possess certain characteristics and exhibit certain behaviors. There are no clear answers yet,but two distinct schools of thought on the matter have developed. As one might expect,the two approaches are very different from each other. The controversy is often conveniently referred to as “nature vs. nurture.”
（62） Those who support the “nature” side of the conflict believe that our personalities and behavior patterns are largely determined by biological factors. （63） That our environment has little,if anything,to do with our abilities, characteristics and behavior is central to this theory.
Taken to an extreme,this theory maintains that our behavior is pre-determined to such a great degree that we are almost completely governed by our instincts.
Those who support the “nurture” theory,that is,they advocate education,are often called behaviorists. They claim that our environment is more important than our biologically based instincts in determining how we will act. A behaviorist,B. F. Skinner,sees humans as beings whose behavior is almost completely shaped by their surroundings.
（64） The behaviorists maintain that,like machines,humans respond to environmental stimuli as the basis of their behavior.
Let us examine the different explanations about one human characteristic,intelligence,offered by the two theories.
（65） Supporters of the “nature” theory insist that we are born with a certain capacity for learning that is biologically determined. Needless to say： They don''t believe that factors in the environment have much influence on what is basically a predetermined characteristic. On the other hand,behaviorists argue that our intelligence levels are the product of our experiences.
（66） Behaviorists suggest that the child who is raised in an environment where there are many stimuli which develop his or her capacity for appropriate responses will experience greater intellectual development.
The social and political implications of these two theories are profound. （67） In the United States,blacks often score below whites on standardized intelligence tests. This leads some “nature”proponents to conclude that blacks are biologically inferior to whites.
（68） Behaviorists,in contrast,say that differences in scores are due to the fact that blacks are often deprived of many of the educational and other environmental advantages that whites enjoy.
Most people think neither of these theories can yet fully explain human behavior.