Intelligence: Environment vs. Genetics

For the record, I have little tolerance for these endless environment vs. genetics debates. Too often, they make it sound like an either-or debate: Either trait X is “determined” by the environment or by genetics. It has to be one or the other. People who actually study this issue have long ago realized that traits are instead “determined” by some combination of the two factors. True, there is a continuum, where some traits may be more influenced by one of these two factors than the other. But it never reaches 100%. It is similarly silly to say that a given trait is “90% genetic” or whatever. This would be like saying that your mother’s apple pie is determined 90% by recipe and 10% by cooking skill. An apple pie is a result of the interplay of these two determinants. You can never completely isolate one factor from the other—or assign a percentage to each one.

That said, it is also my belief that most human characteristics, both physical and behavioral, are significantly influenced by our genes. Just because an apple pie is not 100% determined by its recipe does not mean that its recipe is irrelevant to how the apple pie tastes. The same is true for genes and human behavior.

When it comes to human behaviors and skills, our genes place upper limits on what we can achieve. I doubt that anyone believes they could match Michael Jordan’s basketball abilities simply by practicing harder or getting the “right” training or growing up in a different environment or whatever else might be mentioned here. Most of us will never and could never be as good as Michael Jordan, no matter what. He started off with a genetic advantage that the rest of us don’t have. In a different environment, he might not have realized his potential. But most of us don’t even have the potential to realize.

This reminds me of a more personal example. I took piano lessons for 10 years, from about the age of 8 to 18. For most of that time, I studied under an excellent teacher and studied quite hard. Still, I struggled to move up the ranks and join the teacher’s “advanced students” group. I eventually made it but it was not easy.

Meanwhile, a friend of mine (we weren’t close friends but we were friendly to each other) was taking lessons from the same teacher. We grew up in the same town, were of the same religion and traveled in similar social circles. My friend had a much much easier time advancing. Indeed, he was so good that the teacher wound up giving him his own solo concert when we were seniors in high school. Quite simply, my friend was incredibly talented.

I was not surprised when, several years later, I discovered that my friend had made a career in music. His name is Randy Edelman and he went on to become a noted film composer. I am confident that there is no way that I could have achieved what Randy achieved, no matter how similar our backgrounds and how hard I tried. There was a genetic component to his talent that I did not have.

I was reminded of all of this when I read the recent article in the New York Times by Richard Nisbett, titled “All Brains Are the Same Color.” The main contention of the article is that any racial difference in intelligence “has environmental, not genetic, causes.”

Leaving aside my prior concern about whether such statements are ever meaningful, and leaving aside concerns about the potential bias of I.Q. testing, I would mainly agree with Nisbett’s contention. It is possible that there is a “genetic cause” for some of the difference, just as there may be for any physical trait, such as the color of skin. But, if there is, it is too entangled in other causes for us to clearly define it. At least for the moment, it is more reasonable to assume no difference at all.

But we have to be careful not to overgeneralize here. It is one thing to say that the intelligence differences between two groups have no genetic basis. It is quite another thing to say that there is no genetic basis for intelligence at all. To me this would be the equivalent of saying that we can all be Einsteins, given the right environment. Or that we can all be Michael Jordan. Or that I could have easily been Randy Edelman. It just isn’t so. Pretending it is so or wishing it were so, does not change that fact.

At some level, we all know that some of us are smarter than most of us, and that such differences are not simply a question of environment. Denying this truth, as with the case of any denial of truth, ultimately causes more harm than good.

Sorry for the long gap between this posting and the previous one. I have been busy finishing up my iPhone book. I hope to return to a more frequent posting schedule now.

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