I need some assistance with these assignment. nature vs. nurture in intelligence Thank you in advance for the help! This suggestion became know as eugenics, “the study of the agencies under social control that may improve or repair the racial qualities of future generations, either physically or mentally.” Galton wanted to speed up the process of natural selection, stating that: “What Nature does blindly, slowly, and ruthlessly, the man may do providently, quickly, and kindly”.

Galton was convinced that “intelligence must be bred, not trained”. Such arguments have had massive social consequences and have been used to support apartheid policies, sterilization programs, and other acts of withholding basic human rights from minority groups.

In the heyday of eugenic IQ testing in the 1920s, there was no evidence for the heritability of IQ. It was just an assumption of the practitioners. Today that is no longer the case. The heritability of IQ (whatever IQ is!) is now a hypothesis that has been tested – on twins and adoptees. The results really are quite startling. No study of the causes of intelligence has failed to find a certain and often substantial heritability. What varies from study to study is the amount that can be attributed to heritability.

Evidence in favor of “nurture”

“Give me a dozen healthy infants & my own specific world to bring

them up in, & I’ll guarantee to take anyone at random & train him to

become any type of specialist I might select – doctor, lawyer, artist,

merchant, chef & yes, even beggar & thief, regardless of his talents,

penchants, tendencies, abilities, vocations, and race of his ancestors.”

– John B. Watson, 1924

This was a famous quote in the heyday of behaviorism when the child was considered to be a ‘tabula rasa’ (blank slate) onto which anything could be sculpted through environmental experience. This would be a 100% environmental view, but virtually no psychologists would accept such an extreme position today.

So, what can we say about nature vs. nurture as causal determinants of intelligence

A conservative, seemly safe position is that:

“In the field of intelligence, there are three facts about the transmission of intelligence that virtually everyone seems to accept:

1. Both heredity and environment contribute to intelligence.

2. Heredity and environment interact in various ways.

3. Extremely poor as well as highly enriched environments can interfere with the realization of a person’s intelligence, regardless of the person’s heredity” (Sternberg & Grigorenko, 1997, p.xi).

4. Although most would accept a causal role of genetics, the exact genetic link and how it operates is very far from being understood – another point that most psychologists would agree on. It is certainly not a single gene.