All 237 of them. Although they simplify the hundreds into 4 meta categories, researchers Cindy M. Meston and and David M. Buss have attempted for the first time to catalogue all of the reasons that humans have sex. (You can read the original article here. WARNING: PDF) By breaking motivations for sex into 4 huge categories (physical, goal attainment, emotional, and insecurity), Meston and Buss endeavor to explain the complexities of what was originally thought to be a pretty simple question. Researchers long assumed that there were three basic reasons that people have sex: to reproduce, to experience pleasure, and to relieve sexual tension, but no more. Their list includes things that seem incredibly obvious (I was attracted to the person) to the things that never would have occurred to me (to give my partner an STD). And some of them seem really, really redundant. What’s the distinction between “I was sexually aroused and wanted the release” and “I was ‘horny'”? Or “I wanted the pure pleasure” and “I wanted to experience the physical pleasure”? Hell, what even really distinguishes those four? I have no idea.
As it is, the article has some significant rejoinders to conventional wisdom. For example, the authors refute what one might call the gold digger myth: that women have sex to obtain resources and to sink their claws into an unsuspecting man’s wallet. Men were far more likely than women to admit to having a sexual relationship for purposes of getting a promotion, a raise, or a favor. They were also far more likely to cite the importance of proverbial arm candy in explaining why they were having sex.
While Tierney focuses on the points that either confirm or deny conventional wisdom, I find both the authors’ explanations of their results and possible sources of error to be the most fascinating part. (I mean, was I really supposed to be surprised that people do have sex because they feel obligated to do so? Or because they want to express affection for a partner?)
A gender-role perspective might explain this finding in terms of differences in the gender appropriateness of sexual constraint (i.e., females should be more restrained than males). If having sex (and lots of it) is something that society and evolution* have deemed successful men do (i.e., agentic, powerful, competent), then acting in this manner would be consistent with societal expectations for men. For women, however, endorsing reasons for having sex other than love, commitment, and reproduction would be inconsistent with societal expectancies. Thus, in order for a woman to do so, and to report doing so, she would necessarily need to be less concerned about social dictates and this might reflect an underlying cold and dominant personality style. In support of this explanation, disagreeableness (a trait linked to coldness and dominance) was strongly associated with each of the subfactors for having sex.
As with all self-report studies about sexual behavior, there is always the question as to whether or not your respondents are being truthful or conforming to expectations, and I think this part of the authors’ analysis is spot on. Questions about sex are loaded with cultural expectations and it can be difficult to get people to admit that they’re not within the acceptable range of behavior. The authors go on to point out that women who score higher on personality tests for disagreeableness and unconscientious are more likely to report more sexual partners, which at first makes it sound like only mean and irresponsible women have lots of partners, but really just illuminates the fact that if a woman doesn’t care what people think, she’s far more likely to buck expectations.
As far as reporting issues go, I am also concerned about the article’s discussion (or lack thereof) of rape. The article uses the word rape one time in the body of the paper and the term wasn’t included in the survey itself. (There were several choices: “I was afraid to say no due to the possibility of physical harm”, “I was physically forced”, “The person demanded I have sex with him or her”, “I was pressured into doing it”, “I was verbally coerced into doing it”.) Further, when talking about rape, the authors specifically only mentioned the two responses which address physical harm or threats. Given the overall significance of rape, particularly in their study population: mostly undergraduate and graduate students, I would have thought that this point required more inquiry.
And then there’s this, which made my stomach turn:
Men showed significantly greater endorsement of having sex due to physical reasons, such as “The person had a desireable body”; “The person was too hot (sexy) to resist”; and simply because the opportunity presented itself: “The person was available”; “The person had too much to drink and I was able to take advantage of them.
(Emphasis added)
It’s a little jarring to read an admission of rape in a scholarly article, but there you have it.
*One: this shouldn’t be phrased as a hypothetical. Two: evolution doesn’t “deem” anything. It’s not an agent.