Geoffrey Miller is an evolutionary psychology professor at University of New Mexico. He is the author of  The Mating Mind,  Mating Intelligence ,  Spent , and  What Women Want . His research has focused on sexual selection, mate choice, human sexuality, intelligence, humor, creativity,personality traits, evolutionary psychopathology, behavior genetics, consumer behavior,evolutionary aesthetics, research ethics, virtue signaling, and Effective Altruism. He did a podcast called  The Mating Grounds ; you can follow him on Twitter @primalpoly.

An anonymous male software engineer recently distributed a  memo titled ‘Google’s Ideological Echo Chamber’. Within hours, this memo unleashed a firestorm of negative commentary, most of which ignored the memo’s evidence-based arguments. Among commentators who claim the memo’s empirical facts are wrong, I haven’t read a single one who understand sexual selection theory, animal behavior, and sex differences research.

When the memo went viral, thousands of journalists and bloggers transformed themselves overnight from not understanding evolutionary psychology at all to claiming enough expertise to criticize the whole scientific literature on biological sex differences. It was like watching Trinity downloading the pilot program for flying the B-212 helicopter in The Matrix. Such fast learners! (Even Google’s new ‘VP of Diversity’, Danielle Brown, criticized the memo because it ‘advanced incorrect assumptions about gender’; I was impressed to see that her Michigan State B.A. in Business and her U. Michigan M.B.A. qualify her to judge the scientific research.)

For what it’s worth, I think that almost all of the Google memo’s empirical claims are scientifically accurate. Moreover, they are stated quite carefully and dispassionately. Its key claims about sex differences are especially well-supported by large volumes of research across species, cultures, and history. I know a little about sex differences research. On the topic of evolution and human sexuality, I’ve taught for 28 years, written 4 books and over 100 academic publications, given 190 talks, reviewed papers for over 50 journals, and mentored 11 Ph.D. students. Whoever the memo’s author is, he has obviously read a fair amount about these topics. Graded fairly, his memo would get at least an A- in any masters’ level psychology course. It is consistent with the scientific state of the art on sex differences. (Blank slate gender feminism is advocacy rather than science: no gender feminist I’ve met has ever been able to give a coherent answer to the question ‘What empirical findings would convince you that psychological sex differences evolved?’)

Here, I just want to take a step back from the memo controversy, to highlight a paradox at the heart of the ‘equality and diversity’ dogma that dominates American corporate life. The memo didn’t address this paradox directly, but I think it’s implicit in the author’s critique of Google’s diversity programs. This dogma relies on two core assumptions:

The obvious problem is that these two core assumptions are diametrically opposed.

Let me explain. If different groups have minds that are precisely equivalent in every respect, then those minds are functionally interchangeable, and diversity would be irrelevant to corporate competitiveness. For example, take sex differences. The usual rationale for gender diversity in corporate teams is that a balanced, 50/50 sex ratio will keep a team from being dominated by either masculine or feminine styles of thinking, feeling, and communicating. Each sex will counter-balance the other’s quirks. (That makes sense to me, by the way, and is one reason why evolutionary psychologists often value gender diversity in research teams.) But if there are no sex differences in these psychological quirks, counter-balancing would be irrelevant. A 100% female team would function exactly the same as a 50/50 team, which would function the same as a 100% male team. If men are no different from women, then the sex ratio in a team doesn’t matter at any rational business level, and there is no reason to promote gender diversity as a competitive advantage.

Likewise, if the races are no different from each other, then the racial mix of a company can’t rationally matter to the company’s bottom line. The only reasons to value diversity would be at the levels of legal compliance with government regulations, public relations virtue-signalling, and deontological morality – not practical effectiveness. Legal, PR, and moral reasons can be good reasons for companies to do things. But corporate diversity was never justified to shareholders as a way to avoid lawsuits, PR blowback, or moral shame; it was justified as a competitive business necessity.

So, if the sexes and races don’t differ at all, and if psychological interchangeability is true, then there’s no practical business case for diversity.

On the other hand, if demographic diversity gives a company any competitive advantages, it must be because there are important sex differences and race differences in how human minds work and interact. For example, psychological variety must promote better decision-making within teams, projects, and divisions. Yet if minds differ across sexes and races enough to justify diversity as an instrumental business goal, then they must differ enough in some specific skills, interests, and motivations that hiring and promotion will sometimes produce unequal outcomes in some company roles. In other words, if demographic diversity yields any competitive advantages due to psychological differences between groups, then demographic equality of outcome cannot be achieved in all jobs and all levels within a company. At least, not without discriminatory practices such as affirmative action or demographic quotas.

So, psychological interchangeability makes diversity meaningless. But psychological differences make equal outcomes impossible. Equality or diversity. You can’t have both.

Weirdly, the same people who advocate for equality of outcome in every aspect of corporate life, also tend to advocate for diversity in every aspect of corporate life. They don’t even see the fundamentally irreconcilable assumptions behind this ‘equality and diversity’ dogma.

Why didn’t the thousands of people working to promote equality and diversity in corporate America acknowledge this paradox? Why did it take a male software engineer at Google who’s read a bunch of evolutionary psychology? I suspect that it’s a problem of that old tradeoff between empathizing and systematizing that I wrote about in this  Quillette article on neurodiversity and free speech. The high empathizers in HR and the diversity industry prioritize caring for women and minorities over developing internally coherent, evidence-based models of human nature and society. High systematizers, such as this memo’s author, prioritize the opposite. Indeed, he explicitly calls for ‘de-emphasizing empathy’ and ‘de-moralizing diversity’, arguing that ‘being emotionally unengaged helps us better reason about the facts’. He is right.

His most important suggestion though is apparently the most contentious: ‘Be open about the science of human nature’. He writes ‘Once we acknowledge that not all differences are socially constructed or due to discrimination, we open our eyes to a more accurate view of the human condition which is necessary if we actually want to solve problems.’ This is also correct. If American businesses want to remain competitive in a global market, they must open their eyes to the research, and ground their policies in the known facts about the genetic evolution of sex differences, rather than blank slate delusions about the ‘social construction of gender’.

American businesses also have to face the fact that the demographic differences that make diversity useful will not lead to equality of outcome in every hire or promotion. Equality or diversity: choose one. In my opinion, given that sex differences are so well-established, and the sexes have such intricately complementary quirks, it may often be sensible, in purely practical business terms, to aim for more equal sex ratios in many corporate teams, projects, and divisions.The evolutionary psychology research on sex differences is one of the best reasons to promote sexual diversity in the workplace – and one of the best reasons to expect that there may still be some inequalities of outcome in particular jobs, companies, and industries.