"The Spectrum of Sex" Book Review

Half of our society has come down with what appears to be a form of rapid onset amnesia regarding the existence of biological sex. Just a few years ago nobody could have dreamt of publicly stating that biological sex—the existence of males and females—was a social construct or that they existed along a spectrum. Not without paying a massive social cost, anyway. But now, on a segment of the political left, such pronouncements are commonplace, and failure to mouth the appropriate beliefs (or at least nod along as other do) can have serious professional consequences.

When I first started raising concern several years ago about the rampant sex denialism becoming increasingly evident in our society, colleagues of mine insisted I was being alarmist. Surely nobody was saying that sex was a social construct. Surely I had simply misheard or misread them, and they were actually referring to gender, which is a form of expression, don’t you know? And if some people were denying the reality of biological sex, surely I was blowing it all out of proportion. A colleague had told me I was wasting my time arguing with these people because, in their view, I was essentially arguing with the biological equivalent of Flat Earthers—people so fringe that I’d be better off just ignoring them since there was no way such insanity could ever go mainstream.

Fast forward a couple of years and that insanity is mainstream, and that same colleague who had denounced the belief as fringe has now joined in the chorus. Indeed, the belief that sex is a spectrum or social construct has now become de rigueur within the walls of academia.

I’m not sure what to make of this. Did they actually change their mind? Have they reinterpreted those ostensibly absurd claims in a more palatable form that they can somehow swallow? Are they lying to themselves and others to preserve their jobs? It’s hard to say.

One book that many of my former academic colleagues now frequently cite as the definitive work supporting the spectrum model of biological sex is The Spectrum of Sex: The Science of Male, Female, and Intersex by intersex activist Hida Viloria and biologist Maria Nieto, published in February 2020. The book claims to be a “transformative guide” that “completely breaks down our current understanding biological sex.” One of the reviews in the book by Denice Lombard, an intersex woman and “Racial Justice and Anti-War Activist,” states that “It's time to take off the blinders and recognize and embrace the reality of a third sex—intersex, a diverse biological spectrum between male and female.” The book also promises to introduce readers to “seven variations of human sex” and claims that it’s “the essential introduction to sex and gender diversity” for courses in biology and genetics.

With claims as bold and reviews as glowing as these, it is a work that can’t be ignored. I am always looking to grapple with the best arguments for a position, and this book is frequently cited by academics as being just that. I certainly don’t want to be viewed as only engaging with unsophisticated arguments forwarded by deranged activists on Tumblr. If biological sex really is a spectrum, and there is a good evidence-based argument for it, I want to hear it.

With that in mind, here’s the plan:

I am going to read this book assuming that it has a lot to teach me. I am going to take its arguments very seriously, and I will post a review of each chapter every week as I make my way through it. My goal isn’t to “debunk” each chapter, because that is not my agenda going into this. I will do my best to be charitable and concede points wherever possible. In fact, no outcome would make me happier than having this book thoroughly debunk me and the articles I’ve written on why sex is not a spectrum because I do not wish to remain wrong a moment longer than I have to on such an important issue.

The review of Chapter 1 will be a free post, but all subsequent reviews will alternate between being subscriber-only and free. So the reviews of chapters 1, 3, 5, and 7 will be free, and chapters 2, 4, 6, and 8 will be subscribers-only content.

I have already started reading, and I can tell you right now that I think this is going to be a fun and educational series. I really hope you enjoy it.

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