What Makes Incest Morally Wrong?

There are many things that people generally tend to view to be disgusting or otherwise unpleasant. Certain shows, like Fear Factor, capitalize on those aversions, offering people rewards if they can manage to suppress those feelings to a greater degree than their competitors. Of the people who watched the show, many would probably tell you that they would be personally unwilling to engage in such behaviors; what many do not seem to say, however, is that others should not be allowed to engage in those behaviors because they are morally wrong. Fear or disgust-inducing, yes, but not behavior explicitly punishable by others. Well, most of the time, anyway; a stunt involving drinking donkey semen apparently made the network hesitant about airing it, likely owing to the idea that some moral condemnation would follow in its wake. So what might help us differentiate between understanding why some disgusting behaviors – like eating live cockroaches or submerging one’s arm in spiders – are not morally condemned while others – like incest – tend to be?

Emphasis on the “tend to be” in that last sentence.

To begin our exploration of the issue, we could examine some research on some cognitive mechanisms for incest aversion. Now, in theory, incest should be an appealing strategy from a gene’s eye perspective. This is due to the manner in which sexual reproduction works: by mating with a full sibling, your offspring would carry 75% of your genes in common by descent, rather than the 50% you’d expect if you mated with a stranger. If those hyper-related siblings in turn mated with one another, after a few generations you’d have people giving birth to infants that were essentially genetic clones. However, such inbreeding appears to carry a number of potentially harmful consequences. Without going into too much detail, here are two candidate explanations one might consider for why inbreeding isn’t a more popular strategy: first, it increases the chances that two harmful, but otherwise rare, recessive alleles will match up with on another. The result of this frequently involves all sorts of nasty developmental problems that don’t bode well for one’s fitness.

A second potential issue involves what is called the Red Queen hypothesis. The basic idea here is that the asexual parasites that seek to exploit their host’s body reproduce far quicker than their hosts tend to. A bacteria can go through thousands of generations in the time humans go through one. If we were giving birth to genetically-identical clones, then, the parasites would find themselves well-adapted to life inside their host’s offspring, and might quickly end up exploiting said offspring. The genetic variability introduced by sexual reproduction might help larger, longer-lived hosts keep up in the evolutionary race against their parasites. Though there may well be other viable hypotheses concerning why inbreeding is avoided in many species, the take-home point for our current purposes is that organisms often appear as if they are designed to avoid breeding with close relatives. This poses many species with a problem they need to solve, however: how do you know who your close kin are? Barring some effective spatial dispersion, organisms will need some proximate cues that help them differentiate between their kin and non-kin so as to determine which others are their best bets for reproductive success.

We’ll start with perhaps the most well-known of the research on incest avoidance in humans. The Westermarck effect refers to the idea that humans appear to become sexually disinterested in those with whom they spent most of their early life. The logic of this effect goes (roughly) as follows: your mother is likely to be investing heavily in you when you’re an infant, in no small part owing to the fact that she needs to breastfeed you (prior to the advent of alternative technologies). Since those who spend a lot of time around you and your mother are more likely to be kin than those who spend less time in your proximity. That degree of that proximity ought to in turn generate some kinship index with others that would generate disinterest in sexual experiences with such individuals. While such an effect doesn’t lend itself nicely to controlled experiments, there are some natural contexts that can be examined as pseudo-experiments. One of these was the Israeli Kibbutz, where children were predominately raised in similarly-aged, mixed-sex peer groups. Of the approximately 3000 children that were examined from these Kibbutz, there were only 14 cases of marriage between individuals from the same group, and almost all of them were between people introduced to the group after the age of 6 (Shepher, 1971).

Which is probably why this seemed like a good idea.

The effect of being raised in such a context didn’t appear to provide all the cues required to trigger the full suite of incest aversion mechanisms, however, as evidenced by some follow-up research by Shor & Simchai (2009). The pair carried out some interviews with 60 of the members of the Kibbutz to examine the feelings that these members had towards each other. A little more than half of the sample reported having either moderate or strong attractions towards other members of their cohort at some point; almost all the rest reported sexual indifference, as opposed to the typical kind of aversion or disgust people report in response to questions about sexual attraction towards their blood siblings. This finding, while interesting, needs to be considered in light of the fact that almost no sexual interactions occurred between members of the same peer group; it should also be considered in light of the fact that there did not appear to exist any strong moral prohibition against such behavior.

Something like a Westermarck effect might explain why people weren’t terribly inclined to have intercourse with their own kin, but it would not explain why people think that others having sex with close kin is morally wrong. Moral condemnation is not required for guiding one’s own behavior; it appears more suited for attempting to guide the behavior of others. When it comes to incest, a likely other whose behavior one might wish to guide would be their close kin. This is what led Lieberman et al (2003) to deliver some predictions about what factors might drive people’s moral attitudes about incest: the presence of others who are liable to be your close kin, especially if those kin are of the opposite sex. If duration of co-residence during infancy is used a proximate input cue for determining kinship, then that duration might also be used as an input condition for determining one’s moral views about the acceptability of incest. Accordingly, Lieberman et al (2003) surveyed 186 individuals about their history of co-residence with other family members and their attitudes towards how morally unacceptable incest is, along with a few other variables.

What the research uncovered was that duration of co-residence with an opposite-sex sibling predicted the subject’s moral judgments concerning incest. For women, the total years of co-residence with a brother was correlated with judgments of wrongness for incest at about r = 0.23, and that held whether the time period from 0 to 10 or 0 to 18 was under investigation; for men with a sister, a slightly higher correlation emerged from 0 to 10 years (r = 0.29), but an even-larger correlation was observed when the period was expanded to age 18 (r = 0.40). Further, such effects remained largely static even after the number of siblings, parental attitudes, sexual orientation, and the actual degree of relatedness between those individuals was controlled for. None of those factors managed to uniquely predict moral attitudes towards incest once duration of co-residence was controlled for, suggesting that it was the duration of co-residence itself driving these effects of moral judgments. So why did this effect not appear to show up in the case of the Kibbutz?

Perhaps the driving cues were too distracted?

If the cues to kinship are somewhat incomplete – as they likely were in the Kibbutz – then we ought to expect moral condemnation of such relationships to be incomplete as well.¬† Unfortunately, there doesn’t exist much good data on that point that I am aware of, but, on the basis of Shor & Simchai’s (2009) account, there was no condemnation of such relationships in the Kibbutz that rivaled the kind seen in the case of actual families. What their account does suggest is that more cohesive groups experienced less sexual interest in their peers; a finding that dovetails with the results from Lieberman et al (2003): cohesive groups might well have spent more time together, resulting in less sexual attraction due to greater degrees of co-residence. Despite Shor & Simchai’s suggestion to the contrary, their results appear to be consistent with a Westermarck kind of effect, albeit an incomplete one. Though the duration of co-residence clearly seems to matter, the precise way in which it matters likely involves more than a single cue to kinship. What connection might exist between moral condemnation and active aversion to the idea of intercourse with those one grew up around is a matter I leave to you.

References: Lieberman, D., Tooby, J., & Cosmides, L. (2003). Does morality have a biological basis? An empirical test of the factors governing moral sentiments relating to incest. Proceedings of the Royal Society of London B, 270, 819-826.

Shepher, J. (1971). Mate Selection Among Second Generation Kibbutz Adolescents and Adults: Incest Avoidance and Negative Imprinting. Archives of Sexual Behavior, 1, 293-307.

Shor, E. & Simchai, D. (2009). Incest Avoidance, the Incest Taboo, and Social Cohesion: Revisiting Westermarck and the Case of the Israeli Kibbutzim. American Journal of Sociology, 114, 1803-1846,

Intentional Or Not, Incest Is Still Gross (And Wrong)

For a moment, let’s try to imagine a world that isn’t our own. In this world, the intentions behind an act are completely disregarded when it comes to judging that act morally; the only thing that matters is the outcome. In this world, a man who trips and falls down the stairs, accidentally hitting another man on the way down, is just as wrong as the man who walks up to another and angrily punches him right in the face. In another case, a sniper tries to assassinate the president of the country, but since he misses by an inch no one seems to care.

Such a world would be a strange place to us, yet our sense of disgust seems to resemble the psychology of that world to some degree. While intent doesn’t stop mattering altogether when it comes to disgust, it would seem to matter in a different way than is typically envisioned when it comes to the domain of physical harm.

Sure, it may look disgusting – morally or otherwise – but who doesn’t love Red Velvet?

A recent paper by Young & Saxe (2011) set out to examine the role that intentions placed in the contexts of a more physical harm – poisoning – relative to their role in contexts that elicited disgust – the ever popular case of sibling incest. Subjects read stories in which incest was committed or a friend served another friend peanuts despite knowing about their friend’s peanut allergy; for these stories there was a bad intent and a bad outcome. When both acts were committed intentionally, harm tended to be rated as slightly more morally wrong than incest (6.68 vs 6.03, out of 7). However, the story changed when both acts were committed by accident – when there was still a bad outcome, but only neutral intentions. While the harm condition was now rated as not very wrong, the incest condition was still rated as fairly wrong (2.05 vs 4.24, out of 7).

Another study basically replicated the results of the first, but with one addition: there was now an attempt condition in which an actor intends to commit an act (either harm someone or commit incest), but fails to do so. While the intentional condition (bad intent and bad outcome) was rated as the worst for both incest and harm, and the accidental condition (neutral intent and bad outcome) saw incest rated as worse than harm, the attempt condition showed a different pattern of results: while attempted harm was rated to be just as bad as intentional harm (6.0 and 6.5, respectively), attempted incest was rated more leniently than intentional incest (4.2 and 6.4). In other words, moral judgments of incest were more outcome dependent, relative to moral judgments of harm.

One final study on the topic looked at two different kinds of failed attempts concerning incest and harm: the ‘true belief but failed act’ and the ‘false belief but completed act’. The former involved (in the case of incest) two siblings correctly believe they’re siblings and attempt to engage in intercourse but are interrupted before they complete the act. The latter involved two people who incorrectly believe they’re siblings and actually engage in intercourse. The harm contexts were again outcome independent: whether the harm was completed or not didn’t matter. However, the incest contexts told a different story: the ‘true belief but failed act’ condition¬† was rated as being more immoral than the ‘false belief but completed act’ condition (5.65 vs 4.2). This means subjects were likely rating the act relative to how close it approximated actual incest, and the subjects apparently felt an unconsummated attempt at real incest looked more like incest than a consummated act where the two were just mistaken about their being siblings.

And I think we can all relate to that kind of disappointment…

A further two studies in the paper sought to examine two potential ways to account for this effect. In one case, subjects rated the two stories with respect to how emotionally upsetting they were, how much control over the situation and knowledge of the situation the actors had, and the extent to which the agents were acting intentionally. In no case were there any significant differences, whether concerning disgust or harm, or whether the act was intentional or accidental. The subjects seemed to be assessing the two stories in the same fashion. The second study sought to examine whether subjects were using moral judgments to express the disgust they felt about the story, rather than actually judging the act to be immoral. However, while subjects rated intentional incest as worse than accidental incest, they rated both to be equally as disgusting. Accordingly, it seems unlikely that people were simply using the morality scale as a proxy for their disgust.

It is my great displeasure to have to make this criticism of a paper again, but here goes: while the results are interesting,Young & Saxe (2012) really could have used some theory in this paper. Here’s their stated rationale for the current research:

Our hypothesis was initially motivated by an observation: in at least some cultures, people who commit purity violations accidentally or unknowingly are nevertheless considered impure and immoral.

Observing something is all well and good, but to research it, one should – in my opinion – have a better reason for doing so than just a hunch you’ll see an effect. The closest the authors come to a reasonable explanation of their findings – rather than just a restatement of them – is found in the discussion section, and it takes the form of a single sentence, again feeling like an afterthought, rather than a guiding principle:

…[R]ules against incest and taboo foods may have developed as a means for individuals to protect themselves, for their own good, from possible contamination.

Unfortunately, none of their research really speaks to that possibility. I’d like to quickly expand on that hypothesis, and then talk about a possible study that could have been done to examine it.

Finding an act disgusting is a legitimate reason to not engage it yourself. While that would explain why someone might not want to have sex with their parents or siblings, it would not explain why one would judge others as morally wrong for doing so. For instance, I might not feel inclined to eat insects, but I wouldn’t want someone else punished because they enjoyed doing so. However, within the realm of disgust, the threat of contamination looms large, and pathogens aren’t terribly picky about who they infect. If someone else does something that leads to their becoming infected, they are now a potential infection risk to anyone they interact with (depending on how the pathogen spreads). Accordingly, it’s often not enough to simply avoid engaging in a behavior yourself; one needs to avoid interacting with other infected agents as well. One way to successfully deter people from interacting with you just happens to be aggressive behavior. This might, to some extent, explain the link between disgust and moral judgments. It would also help explain the result that disgust judgments are outcome dependent: even if you didn’t intend to become infected with a pathogen, once you are infected you pose the same risk as someone who was infected more intentionally. So how might we go about testing such an idea?

One quick trip to the bookstore later…

While you can’t exactly assign people to a ‘commit incest’ condition, you could have confederates that do other potentially disgusting things, either intentionally or accidentally, or attempt to do them, but fail (in both cases of the false or true beliefs). Once the confederate does something ostensibly disgusting, you assign them a partner in one of two conditions: interacting at a distance, or interacting in close proximity. After all, if avoiding contamination is the goal, physical distance should have a similar effect, regardless of how it’s achieved. From there, you could compare the willingness of subjects to cooperate or punish the confederate, and check the effect of proximity on behavior. Presumably, if this account is correct, you’d expect people to behave less cooperatively and more selfishly when the confederate had successfully done something disgusting, but this effect would be somewhat moderated by physical distance: the closer the target of disgust is, the more aggressive we’d expect subjects to be.

One final point: the typical reaction to incest – that it’s morally wrong – is likely a byproduct of the disgust system, in this account. Incestuous acts are, to the best of my knowledge, no more likely to spread disease than non-incestuous intercourse. That people tend to find them personally rather disgusting might result in their being hooked onto the moral modules by proxy. So long as morally condemning those who engaged in acts like incest didn’t carry any reliable fitness costs, such a connection would not have been selected against.

References: Young, L., & Saxe, R. (2011). When ignorance is no excuse: Different roles for intent across moral domains Cognition, 120 (2), 202-214 DOI: 10.1016/j.cognition.2011.04.005

Tucker Max, Hitler, And Moral Contagion.

Disgust is triggered off not primarily by the sensory properties of an object, but by ideational concerns about what it is, or where it has been…The first law, contagion, states that “things which have once been in contact with each other continue ever afterwards to act on each other”…When an offensive (or revered) person or animal touches a previously neutral object, some essence or residue is transmitted, even when no material particles are visible. – Haidt et al. (1997, emphasis theirs).

Play time is over; it’s time to return to the science and think about what we can learn of human psychology from the Tucker Max and Planned Parenthood incident. I’d like to start with a relevant personal story. A few years ago I was living in England for several months. During my stay, I managed to catch my favorite band play a few times. After one of their shows, I got a taxi back to my hotel, picked up my guitar from my room, and got back to the venue. I waited out back with a few other fans by the tour bus. Eventually, the band made their way out back, and I politely asked if they would mind signing my guitar. They agreed, on the condition that I not put it on eBay (which I didn’t, of course), and I was soon the proud owner of several autographs. I haven’t played the guitar since for fear of damaging it.

This is my guitar; there are many like it, but this one is mine…and some kind of famous people wrote on it once.

My behavior, and other similar behavior, is immediately and intuitively understandable by almost all people, especially anyone who enjoys the show Pawnstars, yet very few people take the time to reflect on just how strange it is. By getting the signatures on the guitar, I did little more than show it had been touched very briefly by people I hold in high esteem. Nothing I did fundamentally altered the guitar in anyway, and yet somehow it was different; it was distinguished in some invisible way from the thousands of others just like it, and no doubt more valuable in the eyes of other fans. This example is fairly benign; what happened with Planned Parenthood and Tucker Max was not. In that case, the result of such intuitive thinking was that a helpful organization was out $500,000 and many men and women lost access to their services locally. Understanding what’s going on in both cases better will hopefully help people not make mistakes like that again. It probably won’t, but wouldn’t it be nice if did?

The first order of business in understanding what happened is to take a step back and consider the universal phenomenon of disgust. One function of our disgust psychology is to deal with the constant threat of microbial and parasitic organisms. By avoiding ingesting or contacting potentially contaminated materials, the chances of contracting costly infections or harmful parasites are lowered. Further, if by sheer force of will or accident a disgusting object is actually ingested, it’s not uncommon for a vomiting reaction to be triggered, serving to expel as much of the contaminant as possible. While a good portion of our most visceral disgust reactions focus on food, animals, or bodily products, not all of them do; the reaction extends into the realm of behavior, such as deviant sexual behavior, and perceived physical abnormalities, like birth defects or open wounds. Many of the behaviors that trigger some form of disgust put us in no danger of infection or toxic exposure, so there must be more to the story than just avoiding parasites and toxins.

One way Haidt et al. (1997) attempt to explain the latter part of this disgust reaction is by referencing concerns about humans being reminded of their animal nature, or thinking of their body as a temple, which are, frankly, not explanations at all. All such an “explanation” does is push the question back a step to, “why would being reminded of our animal nature or profaning a temple cause disgust?” I feel there are two facts that stand out concerning our disgust reaction that help to shed a lot of light on the matter: (1) disgust reactions seem to require social interaction to develop, meaning what causes disgust varies to some degree from culture to culture, as well as within cultures, and (2) disgust reactions concerning behavior or physical traits tend to focus heavily on behaviors or traits that are locally abnormal in some way. So, the better question to ask is: “If the function of disgust is primarily related to avoidance behaviors, what are the costs and benefits to people being disgusted by whatever they are, and how can we explain the variance?” This brings us nicely to the topic of Hitler.

Now I hate V-neck shirts even more.

As Haidt et al. (1997) note, people tend to be somewhat reluctant to wear used clothing, even if that clothing had been since washed; it’s why used clothing, even if undamaged, is always substantially cheaper than a new, identical article. If the used clothing in question belonged to a particularly awful person – in this case, Hitler – people are even less interested in wearing it. However, this tendency is reversed for items owned by well-liked figures, just like my initial example concerning my guitar demonstrated. I certainly wouldn’t let a stranger draw on my guitar, and I’d be even less willing to let someone I personally disliked give it a signature. I could imagine myself even being averse to playing an instrument privately that’s been signed by someone I disliked. So why this reluctance? What purpose could it possibly serve?

One very plausible answer is that the core issue here is signaling, as it was in the Tucker Max example. People are morally disgusted by, and subsequently try and avoid, objects or behaviors that could be construed as sending the wrong kind of signal. Inappropriate or offensive behavior can lead to social ostracism, the fitness consequences of which can be every bit as extreme as those from parasites. Likewise, behavior that signals inappropriate group membership can be socially devastating, so you need to be cautious about what signal you’re sending. One big issue that people need to contend with is that signals themselves can be interpreted many different ways. Let’s say you go over to a friend’s house, and find a Nazi flag hanging in the corner of a room; how should you interpret what you’re seeing? Perhaps he’s a history buff, specifically interested in World War II; maybe a relative fought in that war and brought the flag home as a trophy; he might be a Nazi sympathizer; it might even be the case that he doesn’t know what the flag represents and just liked the design. It’s up to you to fill in the blanks, and such a signal comes with a large risk factor: not only could an interpretation of the signal hurt your friend, it could hurt you as well for being seen as complicit in his misdeed.

Accordingly, if that signaling model is correct, then I would predict that signal strength and sign should tend to outweigh the contagion concerns, especially if that signal can be interpreted negatively by whoever you’re hoping to impress. Let’s return to the Hitler example: the signaling model would predict that people should prefer to publicly wear Hitler’s actual black V-neck shirt (as it doesn’t send any obvious signals) over wearing a brand new shirt that read “I Heart Hitler”. This parallels the Tucker Max example: people were OK with the idea of him donating money so long as he did so in a manner that kept his name off the clinic. Tucker’s money wasn’t tainted because of the source as much as it was tainted because his conditions made sure the source was unambiguous. Since people didn’t like the source and wanted to reject the perceived association, their only option was to reject the money.

This signaling explanation also sheds light on why the things that cause disgust are generally seen as, in some way, abnormal or deviant. Those who physically look abnormal may carry genes that are less suited for the current environment, or be physically compromised in such a way as it’s better to avoid them than invest in them. Those who behave in a deviant, inappropriate, or unacceptable manner could be signaling something important about their usefulness, friendliness, or their status as a cooperative individual, depending on the behavior. Disgust of deviants, in this case, helps people pick which conspecifics they’d be most profitably served by, and, more generally, helps people fit into their group. You want to avoid those who won’t bring you much reward for your investment, and avoid doing things that get on other people’s bad side. Moral disgust would seem to serve both functions well.

Which is why I now try and make new friends over mutual hatreds instead of mutual interests.

Now returning one final time to the Planned Parenthood issue, you might not like the idea of Tucker Max having his name on a clinic because you don’t like him. I understand that concern, as I wouldn’t like to play a guitar that was signed by members of the Westboro Baptist Church. On that level, by criticizing those who don’t like the idea of a Tucker Max Planned Parenthood clinic, I might seem like a hypocrite; I would be just as uncomfortable in a similar situation. There is a major difference between the two positions though, as a quick example will demonstrate.

Let’s say there’s a group of starving people in a city somewhere that you happen to be charge of. You make all the calls concerning who gets to bring anything into your city, so anyone who wants to help needs to go through you. In response to the hunger problem, the Westboro Baptist Church offers to donate a truck load of food to those in need, but they have one condition: the truck that delivers the food will bear a sign reading “This food supplied courtesy of the Westboro Baptist Church”. If you dislike the Church, as many people do, you have something of a dilemma: allow an association with them in order to help people out, or turn the food away on principle.

For what it’s worth, I would rather see people eat than starve, even if it means that the food comes from a source I don’t like. If your desire to help the starving people eat is trumped by your desire to avoid associating with the Church, don’t tell the starving people you’re really doing it for their own good, because you wouldn’t be; you’d be doing it for your own reasons at their expense, and that’s why you’d be an asshole.

References: Haidt, J., Rozin, P., McCauley, C., & Imada, S. (1997). Body, psyche, and culture: The relationship between disgust and morality. Psychology and Developing Societies, 9, 107-131.

Proximately – Not Ultimately – Anonymous

As part of my recent reading for an upcoming research project, I’ve been poking around some of the literature on cooperation and punishment, specifically second- vs. third-party punishment. Let’s say you have three people: A, B, and X. Person A and B are in a classic Prisoner’s Dilemma; they can each opt to either cooperate or defect and receive payments according to their decisions. In the case of second-party punishment, person A or B can give up some of their payment to reduce the other player’s payment after the choices have been made. For instance, once the game was run, person A could then give up points, with each point they give up reducing the payment of B by 3 points. This is akin to someone flirting with your boyfriend or girlfriend and you then blowing up the offender’s car; sure, it cost you a little cash for the gas, bottle, rag, and lighter, but the losses suffered by the other party are far greater.

Not only does it serve them right, but it’s also a more romantic gesture than flowers.

Third-party punishment involves another person, X, who observes the interaction between A and B. While X is unaffected by the outcome of the interaction itself, they are then given the option to give up some payment of their own to reduce the payment of A or B. Essentially, person X would be Batman swinging in to deliver some street justice, even if X’s parents may not have been murdered in front of their eyes.

Classic economic rationality would predict that no one should ever give up any of their payment to punish another player if the game is a one-shot deal. Paying to punish other players would only ensure that the punisher walks away with less money than they would otherwise have. Of course, we do see punishment in these games from both second- and third-parties when the option is available (though second-parties punish far more than third-parties). The reasons second-party punishment evolved don’t appear terribly mysterious: games like these are rarely one-shot deals in real life, and punishment sends a clear signal that one is not to be shortchanged, encouraging future cooperation and avoiding future losses. The benefits to this in the long-term can overcome the short-term cost of the punishment, for if person A knows person B is unable or unwilling to punish transgressions, person A would be able to continuously take advantage of B. If I know that you won’t waste your time pursuing me for burning your car down – since it won’t bring your car back – there’s nothing to dissuade me from burning it a second or tenth time.

Third-party punishment poses a bit more of a puzzle, which brings us to a paper by Fehr and Fischbacher (2004), who appear to be arguing in favor of group selection (at the very least, they don’t seem to find the idea implausible, despite it being just that). Since third-parties aren’t affected by the behavior of the others directly, there’s less of a reason to get involved. Being Batman might seem glamorous, but I doubt many people would be willing to invest that much time and money – while incurring huge risks to their own life – to anonymously deliver a benefit to a stranger. One of the possible ways third-party punishment could have benefited the punisher, as the authors note, is through reputational benefits: person X punishes person A for behaving unfairly, signaling to others that X is a cooperator and a friend – who also shouldn’t be trifled with – and that kindness would be reciprocated in turn. In an attempt to control for these factors, Fehr and Fischbacer ran some one-shot economic games where all players were anonymous and there was no possibility of reciprocation. The authors seemed to imply that any punishment in these anonymous cases is ultimately driven by something other than reputational self-interest.

“We just had everyone wear one of these. Problem solved”

The real question is do playing these games in an anonymous, one-shot fashion actually control for these factors or remove them from consideration? I doubt that they fully do, and here’s an example why: Alexander and Fisher (2003) surveyed men and women about their sexual history in anonymous and (potentially) non-anonymous conditions. Men reported an average of 3.7 partners in the non-anonymous condition and 4.2 in the anonymous one; women reported averages of 2.6 and 3.4 respectively. So there’s some evidence that the anonymous conditions do help.

However, there was also a third condition where the participants were hooked up to a fake lie detector machine – though ‘real’ lie detector machines don’t actually detect lies – and here the numbers (for women) changed again: 4 for men, 4.4 for women. While men’s answers weren’t particularly different across the three conditions, women’s number of sexual partners rose from 2.6 to 3.4 to 4.4. This difference may not have reached statistical significance, but the pattern is unmistakable.

On paper, she assured us that she found him sexy, and said her decision had nothing to do with his money. Good enough for me.

What I’m getting at is that it should not just be taken for granted that telling someone they’re in an anonymous condition automatically makes people’s psychology behave as if no one is watching, nor does it suggest that moral sentiments could have arisen via group selection (it’s my intuition that truly anonymous one-shot conditions in our evolutionary history were probably rarely encountered, especially as far as punishment was concerned). Consider a few other examples: people don’t enjoy eating fudge in the shape of dog shit, drinking juice that has been in contact with a sterilized cockroach, holding rubber vomit in their mouth, eating soup from a never-used bedpan, or using sugar from a glass labeled “cyanide”, even if they labeled it themselves (Rozin, Millman, & Nemeroff 1986). Even though these people “know” that there’s no real reason to be disgusted by rubber, metal, fudge, or a label, their psychology still (partly) functions as if there was one.

I’ll leave you with one final example of how explicitly “knowing” something (i.e. this survey is anonymous; the sugar really isn’t cyanide) can alter the functioning of your psychology in some cases, to some degree, but not in all cases.

If I tell you you’re supposed to see a dalmatian in the left-hand picture, you’ll quickly see it and never be able to look at that picture again without automatically seeing the dog. If I told you that the squares labeled A and B are actually the same color in the right-hand picture, you’d probably not believe me at first. Then, when you cover up all of that picture except A and B and find out that they actually are the same color you’ll realize why people mistake me for Chris Angel from time to time.Also, when you are looking at the whole picture, you’ll never be able to see A and B as the same color, because that explicit knowledge doesn’t always filter down into other perceptual systems.

References: Alexander, M.G. & Fisher, T.D. (2003). Truth and consequences. Using the bogus pipeline to examine sex differences in self-reported sexuality. The Journal of Sex Research, 40, 27-35

Fehr, E. & Fischbacher, U. (2004). Third-party punishment and social norms. Evolution and Human Behavior, 25, 63-87

Rozin, P., Millman, L., & Nemeroff, C. (1986). Operation of the laws of sympathetic magic in disgust and other domains. Journal of Personality and Social Psychology, 50, 703-712