Heredity or Environment?

In years past, it was believed that children were born with their personalities like blank slates, a formless piece of clay, waiting to be molded by their parents and their environment. Because of the legacy of eugenics from World War II, people were reluctant to consider that psychological traits and behavior disorders might be genetically rooted. Political activists in the 60's and 70's feared that any theories that intelligence or other personality traits were genetically based might be used to justify social inequality, racism and discrimination. It was not considered politically correct to believe that there were limits beyond which a person could not go or that certain abilities and skills were inherited, not learned. According to this thinking, all aspects of personality were learned and everyone had the same underlying potential, if placed in the right environment.

Genes and Nurturing:

New research is now proving what had long been suspected, that many behaviors and most personality traits are genetically controlled and are inherited from our parents. Recent research on mice by Jennifer Brown and Dr. Michael Greenberg has shown that when a certain gene, named fosB was inactivated, that mothers never nurture their young, but leave them to die. The fosB gene is active in the part of the brain that controls nurturing. It is also present in humans, although its role has not been studied. The important thing is, that a behavior such as caring for the young, which some might think is a learned behavior, is in fact controlled by a genetic program in the brains of mice, and possibly humans.


Many studies done in the 1950's focused on the parents of schizophrenics. The mothers were depicted as being rejecting, dominating, cold, overprotective and impervious to the feelings of others. She was said to depend on the child rather than the father for her emotional satisfactions and feelings of completeness as a woman. She was said to dominate, possessively overprotect and smother the child, keeping him dependent and arresting his growth as a person. This was combined with rigid, moralistic attitudes towards sexual behavior which make her overreact with horror to any evidence of sexual impulses on the part of the child. The mother is also seen as overtly seductive in her physical contacts with her son, thus augmenting his sexual conflicts.

The fathers are depicted as being inadequate, indifferent and passive as well as detached and humorless. He was said to be insensitive to the feelings of others, rejecting towards his son and seductive towards his daughter. In short, much of the blame for the schizophrenic's condition was placed on the parents and the home environment.

Today, studies suggest that there is a genetic link to most forms of schizophrenia. The liklihood that a child or sibling of someone with schizophrenia will develop the disease is about 12%, compared to 1% for everyone else. In identical twins, the chances are 50% that the other twin will develop the disease. Researchers suspect that a constellation of genes, working in combination with environmental forces, triggers the disease. There's a lot of information on the web about schizophrenia, but you might want to look at "A Doctor's Guide To Schizophrenia" as a starting place.


The notion that we would all have the same IQ if raised in the same environment has pretty much been debunked. Ongoing major studies are showing clearly that genetics are 50% to 70% responsible for intelligence. There's no question that other factors, such as malnutrition, lead poisoning and physical abuse can lead to a lowering of intelligence. But there has been no convincing evidence that there is any way to raise a person's IQ above what they are born with. Unfortunately, many schools still cling to the myth that all students have an equal ability to learn. They insist on putting lesser gifted students in rigorous academic tracks where they are doomed to failure. They believe that homogeneous grouping is some form of discrimination that must be eliminated at any cost. I refer back to the work of A.S. Neill, who believes that children will rise to their full potential if left alone, and that those who have the desire and ability to become scholars will do so. But those who lack the ability and the motivation will become street sweepers, and that's all right. Our society seems reluctant to give up the Forrest Gump myth that any 75 IQ person can go to college, run a business and become a millionaire. By telling a person they can be anything they want to be is nothing more than selling them a bill of goods. It leads to disappointment, frustration and anger.

For more information on intelligence, check out the Intelligence Page, sponsored by MENSA.

What's It All Mean??

Well, people in this country spend billions of dollars on diets and weight loss programs, much of it going to waste. After all, genes control your body features for the most part, so why bother? If people refuse to believe that their physical appearance is out of their control, how are they going to feel about their personalities being out of their control? Not good, I think And what about the issue of free will? People would like to believe that they have free will and that they have absolute control over their destiny. But if most of human behavior is predicated on our inherited genetic constitution, where does that leave free will? Are we just little automatons, little biochemical machines controlled by a resident computer algorithm which we cannot change? What the heck is going on here? I surely don't know, do you?

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