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【C1】______and another is competitive. Social scientists are, of course, extremely interested in these types of questions. They want to explain why we possess certain characteristics and【C2】______certain behaviors. There are no clear answers yet, but two【C3】______schools of thought on the matter have【C4】______. As one might expect, the two approaches are very different from one another, and there is a great deal of【C5】______between proponents of each theory. The controversy is often【C6】______as "nature v. nurture". Those who support the "nature" side of the conflict believe that our personalities and behavior patterns are【C7】______determined by biological and【C8】______factors. That our environment has【C9】______, if anything, to do with our abilities, characteristics and behavior is central to this theory. Taken to an extreme, this theory【C10】______that our behavior is predetermined to such a great degree that we are almost completely【C11】______by our instincts. Proponents of the "nurture" theory, or,【C12】______they are often called, behaviorists, claim that our environment is more important than our biologically based instincts【C13】______determining how we will act. A behaviorist, B. F. Skinner, sees humans as beings whose behavior is almost completely【C14】______by their surroundings. The behaviorists' view of the human being is quite【C15】______; they maintain that, like machines, humans【C16】______to environmental stimuli as the【C17】______of their behavior. The social and political implications of these two theories are profound. 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. Behaviorists,【C18】______, say that differences in scores are due to the fact that blacks are often deprived of many of the educational and other environmental【C19】______that whites enjoy. Neither of these theories can yet fully explain human behavior. In fact, it is quite likely that the【C20】______to our behavior lies somewhere between these two extremes.