The question is this: How can we distinguish between the environmental causes of behavior and heredity causes? This question embodies the nature-nurture issue. John B. Watson argued that each is made, not born. He discounted the importance of heredity, maintaining that behavior is managed entirely by the environment. Indeed he boldly claimed:

" Give me a dozen healthy infants, well-formed, and my own special world to bring them up in and I'll guarantee to take any one at random and train him to become any type of specialist I might select-doctor, lawyer, artist, merchant-chief, and yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations and race of his ancestors. I am going beyond my facts and I admit it, but so have the advocates of the contrary and they have been doing it for many thousands of years." (Weiten 82)

Although the question was first posed...