More than fifty years after Alfred Kinsey’s discoveries about human sexuality, two neuroscientists have offered what they hope is an improved answer to the question of human sexual desire. To access and analyze the sexual desires of human beings on a mass scale, Ogi Ogas and Sai Gaddam studied the internet use of more than a hundred million men and women across the globe. In their book, A Billion Wicked Thoughts, they share their findings based on their analysis of the websites, erotic videos, and even the digitized romance novels that these users frequent.

Ogas and Gaddam warn the reader in the preface of the explicit nature of their study, and they hold nothing back in presenting a very vivid picture of human sexual tastes. “The sexual brain is guaranteed to upset the politically correct, the socially conservative, and just about everyone in between,” they write, adding that readers are “certain to be challenged and occasionally dumbfounded.”

The first part of their book details the most obvious observations about male and female desire. Men are highly visual and easily aroused by certain parts of the female anatomy. Their search histories show a preference for these feminine parts, as well as a preference for younger women. Women are more complex, and often need many physical and psychological requirements to be met before experiencing arousal. Women are largely attracted to the strength and power status of alpha males. While men often satisfy their desires through pornography, women look to the romance novel. Ogas and Gaddam compare male desire to the cartoon character Elmer Fudd, “wabbit” hunter: Men are “solitary, quick to arouse, goal-oriented, driven to hunt … and a little foolish.” They nickname female desire the “Miss Marple Detective Agency,” for its aim to “uncover, scrutinize, and evaluate a dazzling range of informative clues” present in potential sexual partners. Though men and women seem to share the same brain circuitry governing physical arousal, psychological arousal, sexual reward systems, motivation, and response to sexual cues, Ogas and Gaddam assert that “there are dramatic differences in how these components operate” in the sexes.

To explain these differences, the authors rely on evolutionary theory. Men have developed visual cues to help them identify women who are most likely to provide healthy children for many years to come. Women have developed their complex system of visual and psychological cues in order to identify the men most likely to protect them and their offspring, and they then weigh the various risks associated with pursuing sex.

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Surprising and challenging content follows these chapters, where Ogas and Gaddam detail desires too graphic to recount here (let it suffice to say that BDSM is on the tamer end). It is in these pages that their use of the “adaptationist lens” becomes a problem: Rather than account for their findings by discussing the desire and pleasure systems in the brain already known to us, and how those systems might account for the abnormality of the “politically incorrect” desires they have discovered, Ogas and Gaddam simply explain these desires by proposing other “cues.” For example, to explain why some men are aroused by seeing their wife or girlfriend cheating on them, they suggest a “cuckold cue” that leads to a desire for “cuckold pornography.” To account for some women’s attraction to rapists and paranormal heroes such as vampires and werewolves, the authors conclude that these women must be attracted to men who are, in a sense, the alpha of alphas—extreme loci of male social status and power.

By taking an “adaptationist” approach, Ogas and Gaddam can only conclude that labeling these darker desires as anything other than a healthy part of sexual life is a matter of fearing the unconventional. In their last chapter, they reflect on the diversity of sexual interests that their study revealed, noting that it may be “hard for us to accept that other people’s most intimate desires are different from our own—and when confronted with this fact, we often dismiss their desires as deviant or dangerous or just plain hurtful.” They go on to assert that “science can’t offer any moral prescription about which [sexual] cues should be judged acceptable,” but that “we can accept our fantasies without becoming slaves to them.”

But can we? As evidenced by works such as The Social Costs of Pornography, numerous scholars have agreed that there are myriad harms associated with the pornography industry and with pornography use that reach everyone—individuals, couples, children, the economy, and society at large. Science may not be moral philosophy, but science can help us distinguish what is healthy from what is unhealthy, and it can help us make reasonable, practical, and ethical judgments about behaviors that should and should not be encouraged. And science has spoken quite definitively that pornography should not be encouraged if we are to preserve the health of individuals and communities.

See, for example, the work of neuropsychiatrist Norman Doidge in his book The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science. Building from an explanation of the two pleasure systems that operate in the brain (one that regulates “appetitive” pleasure—the pleasure of desire—and one that regulates “consummatory” pleasure—the pleasure of satisfying desire), Doidge concludes that the brain is quite malleable when it comes to pornography use. New brain maps develop that reinforce the pathways connecting pornographic viewing with excitatory pleasure (and dopamine release).

There is an irony in Doidge’s findings. Contrary to popular culture’s promise that pornography offers a healthy and pleasurable outlet for sexual tension, his research shows that using pornography often only increases and exacerbates such tension. Doidge notes that many of his male patients “often craved pornography but didn’t like it.” For both men and women, exposure to pornography decreases sexual satisfaction with one’s partner. He explains that what pornography “often delivers is an addiction, tolerance, and an eventual decrease in pleasure.”

Journalist Pamela Paul reached similar conclusions in her survey of pornography users. She discovered that for many individuals, using pornography quickly becomes a slippery slope, where users seek out and become habituated to material they once held in disgust, such as “bestiality, group sex, hard-core S&M, genital torture, and child pornography.” For some, this slippery slope quickly leads to a form of addiction.

It would be unreasonable to suggest that all of the subjects that Ogas and Gaddam studied were sex addicts, but in light of the above-cited research, it is reasonable to at least question the subjects’ sexual mental health. Ogas and Gaddam take it for granted that pornography is a normal, healthy part of the human sexual experience. By using widespread internet use to show just how common and “normal” deviant sexual desires and interests are, their methodology takes its cue from the Kinsey mentality that deviant sexual behavior begins in infancy and is not so deviant after all.

Ogas and Gaddam claim that their wide-reaching survey of “millions” improves upon Kinsey’s “landmark” study. To the contrary, they fail in many of the same ways Kinsey did. Kinsey may have surveyed 18,000 subjects for his report, but hundreds of his subjects were sex offenders, prostitutes, prison inmates, and exhibitionists. Another several hundred were mere children. Kinsey’s “science” not only drew from an unrepresentative sample of people, it drew from unhealthy members of society and, in the case of the children studied, from the sexually abused.

Even if we grant that Ogas’s and Gaddam’s research represents the desires of millions, it is a far stretch to claim that their sample is a representative one. Although the amount of online pornography consumed is astounding, only one in four internet users views a pornographic website in a given month. This means that Ogas and Gaddam neglected to account for the sexual desires of the vast majority—75 percent—of people who comprise their target population. Moreover, when one considers current research that details the harmful effects of frequent pornography use on one’s brain and social relationships, there is reason to question whether Ogas’s and Gaddam’s study represents human desire more broadly, as it claims, or whether it reflects the desires of the sexually troubled.

Overall, the authors’ study is limited by subscribing to a type of biological determinism where the sexual cues in our brains determine our desires and thereby excuse them. In this way, Ogas and Gaddam take the ideology of Kinsey a step further. It is both unscientific and unacceptable that the Kinsey reports have been hailed for over half a century as a liberating turning point in American sexual identity, awareness, and health. We would be wise to keep the reports of A Billion Wicked Thoughts from being acclaimed in the same way.