男人每隔多久就会“性”趣盎然？

It's a stat that gets bounced around as e-mail-forward wisdom: men think about sex every seven seconds. Even when the idea lacks this mythical specificity and grandiosity (that's 7,200 times a day!), the idea that men think about sex basically all the time is widespread. And so, it is possible to attach all kinds of bogus statistics to the feeling that men are sex-crazed pigs.

But the actual number of times that men think about sex in a day is not clear-cut in scientific research. There is no perfect technology that taps into one's sexy brain waves.

What researchers really do is come up with clever ways of asking people what they're thinking about. They call it "experience sampling." So, in a recent study, Ohio State University researchers gave people a clicker and were asked to hit one of three buttons on it—sex, food, sleep—every time the thought of one of those things came to mind. Their study showed that the average man had 19 thoughts about sex in a day.

But the design of the study could have influenced the frequency count, writes cognitive scientist Tom Stafford in a new column. If you tell people to try to notice every time they think about something, you might very well increase the frequency of their thoughts about that thing. (Researchers call this the "white bear problem.")

Other researchers—who use different sampling methods—get different results. So, a phone-based survey that asked participants more free-form questions seven times a day found that men think about sex less than they think about "food, sleep, personal hygiene, social contact, time off, and (until about 5 p.m.) coffee."

If you put these two studies together, as Stafford does, it's obvious that the technique influences, if not outright dominates, the phenomenon being studied.

And yet the experience sampling method has gotten more popular, in part because everyone has a little computer in their hands all the time, which makes surveying much, much, much easier. "Smartphones are an ideal platform for conducting Experience Sampling Method (ESM) based studies," a recent review of sampling techniques found.

But it's difficult to judge a person's thoughts, no matter what technology people use. The lead researcher in the Ohio State study, Terri Fisher, provided a self-critique of her study, which applies to many of them.

"We weren't able to study how long the thoughts lasted or the nature of the thoughts. We also don't know if all of our participants followed the instructions and really clicked every time they had the sort of thought that they were supposed to track," Fisher wrote. "However, even if they didn't, the fact that they were supposed to be clicking probably made them more aware of their thoughts about their assigned topic than they might otherwise have been, and that would have been reflected in their daily reports."

The perfect technology would directly measure one's brain activity and somehow translate that into the number of sexual thoughts one had, but even that might prove very difficult. What we call "a thought" is not the discrete thing that we like to pretend. "There’s also the tricky issue that thoughts have no natural unit of measurement," Stafford writes. "Thoughts aren’t like distances we can measure in centimetres, metres and kilometres. So what constitutes a thought, anyway? How big does it need to be to count? Have you had none, one or many while reading this?"

Perhaps the more interesting question is why we want to quantify this kind of thing at all. Does it matter if men think of sex—however defined—12 times a day, or 19, or 7, or 400?

These numbers reduce a whole set of arguments about the relative sexualities and norms of men and women, detaching the feelings from the lived experience of people.

That may be useful rhetoric for proving that men are pigs or women should be chaste or whatever, but the data says more about the limitations of our survey technologies than the nature of human sexuality.

据一封被广为转发的电子邮件中的数据表明：男人每七秒钟就会想到性。虽然这种说法缺乏根据且过于夸张（那可是一天7200次！），但还是广为流传。看来“男人就是种猪”这种说法完全有可能被添油加醋地附上各种不靠谱的数据。

但科学研究还没有就男人每天产生“性”趣的次数提出一个明确的答案。还没有技术能够监测到“人脑性电波”。

但研究人员想到了一个聪明的点子，就是问人们他们在想什么。研究人员将这种方法称之为“体验抽样”。在最近的一项研究中，俄亥俄州立大学的研究人员发给受访者一个点击器，上面有三个按钮，分别代表性、食物、睡眠，受访者被要求每当想到其中之一时便按下相应的按钮。该研究结果显示男人平均每天联想到性的次数是19次。

但认知学专家汤姆·斯塔福德（Tom Stafford）在一期新专栏中写道，这种研究方法的设计原理也许影响了频率的计数结果。如果你让别人在想到某事时试着去记录的话，那么你很可能会提高他想到那件事的频率。（科研人员称之为“白熊效应”，其得名于1978年心理学上著名的“白熊试验”，即，对于事情，你越想忘记，反而记得的越清楚。）

其他研究者采用不同的抽样方法得出了不同的结果。他们采用电话调查的方式，每天七次向受访者问一些宽泛的问题。研究人员发现男人想到性的次数低于想到“食物、睡眠、个人卫生、社交、休假、咖啡（下午五点左右）”的次数。

如果你像斯塔福德一样把这两个研究综合起来看，你就会发现科技会影响男人想到性的次数，虽然不是百分百的影响。

然而“体验抽样”这一研究方法却越来越流行。部分原因是因为现如今人手一部手机使得调查要比过去方便得多。最近一项对抽样技术的研究表明：“智能手机是进行‘体验抽样’的绝佳平台。”

但不管人们使用什么技术，都很难去判定一个人的想法。俄亥俄州立大学研究项目的带头人特芮·费舍尔就对自己的研究做了自我检讨，这些批评同样适用于其他的研究项目。

费舍尔写道：“我们没研究出想法持续的时长或其本质是什么。我们也不知道这些受访者是否遵从指示在每一次想到相应事物的时候都会按下按钮。但是，即使他们没有每次都按，‘要按按钮’这个念头也许会让他们比平时更加在意实验中提到的主题，而这或许就反映在他们每天的反馈数据中。”

完美的技术或许能够直接监测脑部活动并通过某种方式记录下有关性的想法的次数，但即使这样也被证明是很难实现的。所谓“一个想法”并非是我们可以假装出来的一个孤立的东西。斯塔福德写道：“比较棘手的是，想法并不能用单位来度量。它不像距离可以用厘米、米和公里来丈量。所以，到底是什么构成了一个想法？多大的想法才能被算作是一个想法？当你读到这段话的时候，你是毫无想法呢，还是有一个甚至许多想法？”

也许，我们为什么想把男人的“性”趣量化才是个更有意思的问题。不管是每天12次、19次、7次还是400次，男人想到性的次数的多少——无论哪种算法——又有什么意义呢？

这些研究结果得出的数字减少了关于相对性征和男女标准的各种争论，打破了人们生活中“男人就是种猪”的固有认知。

也许从修辞手法来说，以上结论可以证明“男人是猪”或女人应该保持纯洁，不过这些研究数据更多地体现了我们的调查技术的局限性，而非人类性活动的本质。