Nature and Nurture
In practice, hardly anyone today accepts either of the extreme positions. There are simply too many “facts” on both sides of the argument which are inconsistent with an “all or nothing” view.
So instead of asking whether psychological traits are influenced by nature or nurture the question has been reformulated as “How much?” That is to say, given that heredity and environment both influence the person we become, which is the more important?
This question was first framed by Francis Galton in the late 19th century. Galton (himself a relative of Charles Darwin) was convinced that intellectual ability was largely inherited and that the tendency for “genius” to run in families was the outcome of a natural superiority.
This view has cropped up time and again in the history of psychology and has stimulated much of the research into intelligence testing. A modern proponent is the American psychologist Arthur Jenson. Finding that the average I.Q. scores of black Americans were significantly lower than whites he went on to argue that genetic factors were mainly
responsible – even going so far as to suggest that intelligence is 80% inherited.
The storm of controversy that developed around Jenson’s claims was not mainly due to logical and empirical weaknesses in his argument. It was more to do with the social and political implications that are often drawn from research that claims to demonstrate natural inequalities between social groups.
Galton himself in 1883 suggested that human society could be improved by “better breeding.” In the 1920’s the American Eugenics Society campaigned for the sterilization of men and women in psychiatric hospitals. Today in Britain many believe that the immigration policies are designed to discriminate against Black and Asian ethnic groups.
For many environmentalists there is a barely disguised right-wing agenda behind the work of the behavioral geneticists. In their view, part of the difference in the I.Q. scores of different ethnic groups are due to inbuilt biases in the methods of testing.
More fundamentally, they believe that differences in intellectual ability are a product of social inequalities in access to material resources and opportunities. To put it simply children brought up in the ghetto tend to score lower on tests because they are denied the same life chances as more privileged members of society.
Now we can see why the nature-nurture debate has become such a hotly contested issue. What begins as an attempt to understand the causes of behavioral differences often develops into a politically motivated dispute about distributive justice and power in society.
What’s more, this doesn’t only apply to the debate over I.Q. It is equally relevant to the psychology of sex and gender, where the question of how much of the (alleged) differences in male and female behavior is due to biology and how much to culture is just as controversial.