Sam Harris Doesn’t Understand Bell Curves
It’s Thursday and that means it’s time for another round of Bad Chart Thursday. This week, rather than make fun of a bad chart, I was inspired to write a bit about bell curves and more specifically Sam Harris’ complete lack of understanding as to how bell curves work.
You see, the internet blew up this week after a Washington Post profile of Sam Harris written by Michelle Boorstein included the following quote from Harris explaining why such a large proportion of his fan-base are men:
“I think it may have to do with my person slant as an author, being very critical of bad ideas. This can sound very angry to people..People just don’t like to have their ideas criticized. There’s something about that critical posture that is to some degree instrinsically [sic] male and more attractive to guys than to women,” he said. “The atheist variable just has this – it doesn’t obviously have this nurturing, coherence-building extra estrogen vibe that you would want by default if you wanted to attract as many women as men.”
Many people have pointed out how terribly sexist this statement is. Harris then posted a response to all the criticism where he assures us all that he is totally not a sexist in a piece he calls “I’m Not the Sexist Pig You’re Looking For.” Sure, some of his statements may seem sexist, but according to Sam Harris it’s totally not sexist if it’s based in scientific fact and everyone just knows that science says ladies don’t like Sam Harris because of their estrogen-vibe.
I’m sure that many others will scrutinize each aspect of his defense, but I would actually like to focus on one small section where he discusses the differences between variation between groups versus within groups:
My work is often perceived (I believe unfairly) as unpleasantly critical, angry, divisive, etc. The work of other vocal atheists (male and female) has a similar reputation. I believe that in general, men are more attracted to this style of communication than women are. Which is not to say there aren’t millions of acerbic women out there, and many for whom Hitchens at his most cutting was a favorite source of entertainment. But just as we can say that men are generally taller than women, without denying that some women are taller than most men, there are psychological differences between men and women which, considered in the aggregate, might explain why “angry atheism” attracts more of the former. Some of these differences are innate; some are surely the product of culture. Nothing in my remarks was meant to suggest that women can’t think as critically as men or that they are more likely to be taken in by bad ideas. Again, I was talking about a fondness for a perceived style of religion bashing with which I and other vocal atheists are often associated.
Strangely, Harris starts out seemingly understanding how different populations that have variation within them interact and yet comes to exactly the opposite conclusion of where the argument should lead. In order to understand what is going on here, let’s learn a bit about bell curves.
Here is a simple bell curve. In this case, we’re measuring the amount of estrogen-vibe, a thing that Sam Harris seems to think is an innate quality that increases empathy, decreases aggressiveness, and causes a person to harbor a dislike for Sam Harris. To start with, let’s look at the population as a whole. A bell curve shows the proportion of a population with a certain characteristic, in this case estrogen-vibe. The tallest point on the graph is at the mean or average. Most people in the population are somewhere at or near the average. As you move out to the edges of the graph, the curve converges on 0 as there are less and less people who have the extremes of the characteristic. So, just like very few people are taller than 6.5ft or shorter than 5ft, there are few people with super estrogen-vibe who just have to nurture everything they come in contact with and very few people with almost no estrogen-vibe that purportedly spend all day trolling YouTube for new people to yell rape threats at and enjoy reading things written by Sam Harris. The average person may be somewhere in the middle, but the population as a whole has a lot of variation with some people at the extremes.
According to Sam Harris, women as a group have more estrogen-vibe than men. I don’t know what the fuck he is talking about with estrogen-vibe, but he flat out states that there are innate psychological differences between men and women. Many researchers have searched for cognitive and psychological differences between the genders and taken as a whole, researchers have found little to no difference in cognitive ability or psychological differences between men and women and when differences are found, it’s unclear whether they are themselves innate or a product of our culture and experiences. If differences exist at all they are quite small and can only be seen in the aggregate.
Sam Harris believes that there are differences in the aggregate between men and women on the estrogen-vibe scale. We can split our bell curve into two bell curves, one for women and one for men.
As you can see comparing the distribution of women to that of men, the women’s distribution on a whole has a bit more estrogen-vibe than the men’s. The average estrogen-vibe of women is slightly higher than that of the men.
Although the average man may have less estrogen-vibe than the average woman, a very large proportion of women have even less estrogen-vibe than the average man. If we got a room full of people, we would probably not be able to see the differences between men and women if those differences are as slight as the literature seems to suggest. We may be able to see these small population differences if we ran a large, controlled study but it would be practically invisible to us on an individual level as we go about our lives and it certainly wouldn’t result in large gender imbalances in terms of people who like Sam Harris.
This is why population size in studies matter. If the differences you are looking for are small, you will not be able to see them unless you have a proportionally large population in your study. If psychological differences exists at all, it seems to be quite small since most studies find nothing or find only tiny effects. Even if these effects are real, you could not see them out in the world because the sample of men and women you come across as you go about your daily life is just too small to be able to distinguish slight differences. This is why whenever a new evo-psych study comes out that says something like “women are slightly more cooperative than men” and the response from a couple of your annoying facebook friends that you haven’t spoken to since High School is “see, I told you women were just [insert sexist stereotype here]” they are wrong even if the science is right. Small differences in populations just cannot be seen in the small sample of people you meet in your life. Plus, you can’t even measure psychological traits very accurately so you are not going to be able to get accurate enough measurements to see those differences even if they were big enough to see otherwise. Your own judgments and biases are going to be larger than any actual differences between the groups if those differences exist at all.
The only way you would be able to see differences between the psychologies of men and women is if those differences were quite large. If the only thing skewing the gender of Sam Harris fans was estrogen-vibe, then the differences between the genders would have to be immense, something which would completely overturn all prior gender research. So, the real question here is whether Sam Harris has discovered the magical x-factor that makes the brains of men versus women very different. This would certainly be a shock to the science of gender differences because no one has ever found psychological differences that pronounced.
Rather than there being some previously-unknown psychological factor that gives women a completely different brain than men, the thing that makes women different is our lived experiences. Women grow up and move through the world in a completely different environment from men. From the time we are born, we are treated differently, under different expectations, and have different roles within our culture. Lived experience does make us women different in ways that are so large that we can see them without the need of a scientific study. We can all see that men tend to like Sam Harris much more than do women. It is far more likely that something about the experiences of men versus women in our culture is the explanation for the differences rather than some psychological difference in our brains. Perhaps instead of estrogen-vibe as an explanation, the following is a bit more explanatory:
Since women have to live in a world where they face both outright and structural sexism on a daily basis, they are probably much more sensitive to sexism than are most men. Perhaps the reason women don’t seem to like Sam Harris isn’t because they have some magical estrogen-vibe but because he actually is a sexist pig.