By now, most of us have heard about Google's so-called "anti-diversity" manifesto and how James Damore, the engineer who wrote it, has been fired from his job.

Titled Google's Ideological Echo Chamber, Mr. Damore called out the current PC culture, saying the gender gap in Google's diversity was not due to discrimination, but inherent differences in what men and women find interesting. Danielle Brown, Google's newly appointed vice-president for diversity, integrity and governance, accused the memo of advancing "incorrect assumptions about gender," and Mr. Damore confirmed last night he was fired for "perpetuating gender stereotypes."

Despite how it's been portrayed, the memo was fair and factually accurate. Scientific studies have confirmed sex differences in the brain that lead to differences in our interests and behaviour.

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As mentioned in the memo, gendered interests are predicted by exposure to prenatal testosterone – higher levels are associated with a preference for mechanically interesting things and occupations in adulthood. Lower levels are associated with a preference for people-oriented activities and occupations. This is why STEM (science, technology, engineering and mathematics) fields tend to be dominated by men.

We see evidence for this in girls with a genetic condition called congenital adrenal hyperplasia, who are exposed to unusually high levels of testosterone in the womb. When they are born, these girls prefer male-typical, wheeled toys, such as trucks, even if their parents offer more positive feedback when they play with female-typical toys, such as dolls. Similarly, men who are interested in female-typical activities were likely exposed to lower levels of testosterone.

As well, new research from the field of genetics shows that testosterone alters the programming of neural stem cells, leading to sex differences in the brain even before it's finished developing in utero. This further suggests that our interests are influenced strongly by biology, as opposed to being learned or socially constructed.

Many people, including a former Google employee, have attempted to refute the memo's points, alleging that they contradict the latest research.

I'd love to know what "research done […] for decades" he's referring to, because thousands of studies would suggest otherwise. A single study, published in 2015, did claim that male and female brains existed along a "mosaic" and that it isn't possible to differentiate them by sex, but this has been refuted by four – yes, four – academic studies since.

This includes a study that analyzed the exact same brain data from the original study and found that the sex of a given brain could be correctly identified with 69-per-cent to 77-per-cent accuracy.

Of course, differences exist at the individual level, and this doesn't mean environment plays no role in shaping us. But to claim that there are no differences between the sexes when looking at group averages, or that culture has greater influence than biology, simply isn't true.

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In fact, research has shown that cultures with greater gender equity have larger sex differences when it comes to job preferences, because in these societies, people are free to choose their occupations based on what they enjoy.

As the memo suggests, seeking to fulfill a 50-per-cent quota of women in STEM is unrealistic. As gender equity continues to improve in developing societies, we should expect to see this gender gap widen.

This trend continues into the area of personality, as well. Contrary to what detractors would have you believe, women are, on average, higher in neuroticism and agreeableness, and lower in stress tolerance.

Some intentionally deny the science because they are afraid it will be used to justify keeping women out of STEM. But sexism isn't the result of knowing facts; it's the result of what people choose to do with them.

This is exactly what the mob of outrage should be mobilizing for, instead of denying biological reality and being content to spend a weekend doxxing a man so that he would lose his job. At this point, as foreshadowed in Mr. Damore's manifesto, we should be more concerned about viewpoint diversity than diversity revolving around gender.

Debra Soh writes about the science of human sexuality and holds a PhD in sexual neuroscience from York University.