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 【C5】______ are very different from one another, and there is a great deal of 【C6】______ between proponents (支持者) of each theory. The controversy is often 【C7】______ to as 'nature vs nurture'. Those who support the 'nature' side of the conflict believe that our personalities and behavior. patterns are 【C8】______ determined by biological and 【C9】______ factors. That our environment has 【C10】______ , 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 predetermined 【C11】______ such a great degree that we are almost completely 【C12】______ by our instincts. Proponents of the 'nurture' theory, or, 【C13】______ they are often called, behaviorists, claim that our environment is more important than our biologically based instincts in determining 【C14】______ we will act. A behaviorist, B. F. Skinner, sees humans as beings whose behavior. is almost completely 【C15】______ by their surroundings. The behaviorists' view of the human being is quite 【C16】______ they maintain that, like machines, humans 【C17】______ to environmental stimuli as the 【C18】______ of their behavior. Neither of these theories can yet 【C19】______ explain human behavior. In fact, it is quite likely that the 【C20】______ to our behavior. lies somewhere between these two extremes. That the controversy will continue for a long time is certain. 【C1】