Sex, drugs and moral goals: Study of reproductive strategies and recreational drug use

June 16, 2010, University of Pennsylvania

Why is there so much disagreement about whether using recreational drugs is morally wrong? A University of Pennsylvania psychology study shows that the debate about drugs might really be about sex.

The study compared two competing theories.

One theory -- the in -- sees drug attitudes as primarily coming from people's political ideology, level of religious commitment, and personality, for example, openness to experience.

The other theory, proposed by the researchers and driven by ideas from , holds that drug attitudes are really driven by people's reproductive strategies.

When the Penn researchers questioned almost 1,000 people in two subject populations, one undergraduate and one Internet-based, a clear winner emerged between the competing theories: Differences in reproductive strategies are driving individuals' different views on recreational drugs.

While many items predict to some extent whether people are opposed to recreational drugs, the most closely related predictors are people's views on sexual promiscuity. While people who are more religious and those who are more politically conservative do tend to oppose recreational drugs, in both study samples the predictive power of these religious and ideological items was reduced nearly to zero by controlling for items tracking attitudes toward sexual promiscuity.

"This provides evidence that views on sex and views on drugs are very closely related," said Kurzban, associate professor in the Department of Psychology and director of the Pennsylvania Laboratory for Experimental Evolutionary Psychology at Penn. "If you were to measure people's political ideology, religiosity and personality characteristics, you can predict to some degree how people feel about recreational drugs. But if, instead, you just measure how people feel about casual sex, and ignore the abstract items, the predictions about people's views on drugs in fact become quite a bit better."

From a theoretical perspective, the study also concludes that considering morality from the standpoint of strategic reproductive interests is a potentially useful way to understand why humans care about third-party behavior.

According to the researchers' evolutionary model, people develop complex differences in their sexual and reproductive strategies. One key difference that creates strategic conflict arises in people's orientations towards casual sexual activity. The relationships of people following a more committed, monogamous reproductive strategy are put at greater risk when casual sex is prevalent. On the other hand, people pursuing a less committed lifestyle seek to avoid having their choices moralized, forbidden and punished.

The researchers cite prior work showing that recreational drug usage is often associated with promiscuity. The results of the study imply that attitudes against recreational drugs are part of a larger attempt to advance the cause of committed, monogamous reproductive strategies.

"Condemnation of drug usage might be best understood in the context of strategic dynamics, with individuals influencing moral rules in a way that favors their own competitive ," Kurzban said. "We expect that this relationship between sexual strategy and moral stances will occur in other areas as well, such as attitudes toward prostitution, sexual education or abortion."

The research team analyzed questionnaires from 516 undergraduate students from the University of Central Florida and 471 individuals recruited from a Web-based recruitment site, Amazon's Mechanical Turk, or Mturk.

Participants reported their overall liberal/conservative political identification, rated their support or opposition to a number of current political issues and answered questions about their personalities, disgust sensitivity, moral views, sexual attitudes and level of religiosity. The measure of recreational drug attitudes consisted of questions on the morality and legal status of using marijuana, cocaine and Ecstasy, as well as general attitudes towards recreational drugs.

More information: The study is published in the current issue of Proceedings of the Royal Society B.

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5 / 5 (5) Jun 16, 2010
Hopefully, the law with regard to sex and drugs will converge. As long as you are consenting adults in private, I don't see why the state should have any sanction, it should stop at the bedroom door. Maybe in some years time we will regard the prohibition as a bit prissy, and frankly, a bit bonkers - much like we regard the persecution of gay men in the 50's, like Alan Turing. Perhaps there will be an equal opportunities law for stoners? .. Not sure i'd entirely agree, but certainly i think that if a piss test is the only way to tell one applicant from another then its unfair.
On topic, is it not also fear of "freeloaders" - a legitimate society emotion - that shapes attitudes on drug use also? Are the prohibitionists also more willing to dish out social justice to other groups whom they perceive as "cheating"? Is this the link beneath the correlation?
5 / 5 (1) Jun 16, 2010
What I find interesting is that although the drugs attitude correlates strongly to attitudes about sex, it doesn't necessarily correlate to political or religious stance (at least not nearly as strongly. This indicates that political and religious stances are not a strong indicator of sexual attitudes.
not rated yet Jun 17, 2010
What I find interesting is that although the drugs attitude correlates strongly to attitudes about sex, it doesn't necessarily correlate to political or religious stance (at least not nearly as strongly. This indicates that political and religious stances are not a strong indicator of sexual attitudes.

Two words Bill Clinton ;)
1 / 5 (6) Jun 17, 2010
The study seems to confirm that rejecting your creator also leads to rejecting all norms set by that creator:
If you object to having sex only in a marriage between a man and a woman, you'll also soon reject any other teaching from the bible.

Has it not occurred to the professor that people taking drugs tend to get out of control and harm others as a result? Same as with alcohol [also a drug] and cigarette smoke. If there wasn't any harm [to others] arising from such drug usage, I don't think anyone would have objected. No need for any moral/religious/political persuasions. It comes down to that simple question: Are there any harmful consequences down the line by doing this?

Same thing for promiscuity - unwanted children, infectious diseases etc. etc.
Does the professor think it's good to steal, murder, rob and have adulterous affairs? These are in the same category of doing harm to others as drugs. There are consequences down the line. They also tend to accompany drug usage.
not rated yet Jun 17, 2010
Millions of people do in-vitro, strange they didn't mention their own science as a precursor to the abstract rather than casual sex having the equal measurement of distance to recreational drug use.

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