Why cheaters leave a bad taste in your mouth

Our reactions to bad behaviour may have biological roots


 Psychologists at the University of Toronto have found that immoral behaviour triggers the same physiological reactions that enabled early humans to stay away from poisonous foods and infection. The study–published this week in the journal Science—is one of the first to discover that morality has biological roots linked to primitive survival. The study asked participants to drink foul-tasting liquids and look at pictures of filthy toilets, feces or injuries while the disgust and repulsion in their facial expressions were measured by electronic sensors. The volunteers were equally disgusted when they were cheated in games involving money. While researchers say moral disgust doesn’t actually taste bad, it does affect the same neural circuitry as when you taste something foul.


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Why cheaters leave a bad taste in your mouth

  1. Too bad there are not more people who get bad tastes in their mouths.

  2. “one of the first to discover that morality has biological roots linked to primitive survival.”

    I’ll bet it is. God, I love pseudo-science.

    • are you suggesting that morality doesn’t have biological roots?

      • No, but this study presupposes that it’s immoral to cheat somebody! Or at least that’s how the paper is reporting it. It’s interesting that being cheated has a physiological reaction, but it’s hardly a “moral” judgment. Our remote ancestors had a slightly different set of values than pertain in the Annex, I think.

        • Not as I read it – they are saying that our morals today are partly reflective of some biological basis. They aren’t making a judgment as to whether cheating should be morally acceptable today – it is an empirical, not a normative focus. Now, I am skeptical about the existence of a provable, objective system of morality anyway – and I think if you delve into most people’s moral systems it tends to flow back to “what works” or “what worked” (and that isn’t necessarily by design – if different primitive societies chose moral values at random, some societies would fare better than others, and so their moral systems would be more likely to survive today).

          • So what does this prove about morality — ours or anybody’s — except that people (surprise, surprise) don’t like being cheated?

            I mean, if you class “non-enjoyment of being cheated” as “morality,” you’re painting with a pretty big brush.

          • I mean, if you class “non-enjoyment of being cheated” as “morality,” you’re painting with a pretty big brush.

            But the perception of cheating does involve a moral judgment. So it is perfectly legitimate to make a connection between “non-enjoyment of being cheated” and “morality”, without using an oversized brush.

          • For whatever it’s worth, studies of modern foragers (hunters and gatherers) – which was the pattern of subsistence for all humans until 30,000 years ago (when the earliest small-scale horticulture began to emerge) – showed a fairly common tendency towards generalized reciprocity.

            Generalized reciprocity is a pattern of sharing and exchange where people don’t hoard food, nor does the ability to gather or hunt better than other members of the band/tribe give one any rights to extra or better food. In fact, the practice would often be for the successful hunter to take the poorest part of the animal for himself, while sharing the rest.

            There’s an entire symbolic and moral worldview that tends to go along with such arrangements. These societies were fiercely egalitarian – there were no formalized leaders and decisions tended to made by consensus. Among the ultimate ‘sins’ involved being viewed as a hoarder, or stingy, and assuming superiority over others. There were complex social levelling mechanisms that ranged from gossip to ostracism to prevent selfish and controlling behaviour. Even the spiritual view the world (“animism”) that characterizes many/most foraging groups tends to downplay the importance of individuals (and humans, for that matter).

            This is a gross oversimplification, but the pattern was one found amongst most forager groups studied in the early to mid 1900s, and would tend to support the idea that our early ancestors were not big on cheating each other.

            However, like Jack, I’m fairly skeptical of these sorts of studies. For starters, how can we ever know which came first: the biolocial/instinctive or the sociocultural? Also, can someone name a social animal species where cheating behaviour is routine?

            Finally, I’m glad they took pains to point out that moral disgust doesn’t actually have a real taste in the mouth. I would have wondered if I was missing something, otherwise!

          • “the perception of cheating does involve a moral judgment”

            How so? The terms on which the agreement was reached, before it was violated, certainly involve morality; but the fact of an agreement’s violation doesn’t tell us about those terms.

            Sean makes a good point about the communal ethos of our pack-animal days; though I would also point out that it might be quite normal to have one morality for dealing with your fellow pack-members, another for diplomatic relations with other packs, and a third for dealing with enemies. Methinks it was one thing to deceive/cheat your own family, another to do deceive/cheat people outside the group. E.g. Odysseus in the Odyssey is admired precisely for his ability to cheat everybody — Athena commends him on it in Book 13.

            What I find interesting about this study is that it’s a “taste” reaction — as opposed to making people blush, stoop, shiver, etc. I’d suggest this points to food having been the basic item of exchange at the time this reflex developed.

          • SS. Here are some social animals cheating. http://www.livescience.com/animals/080312-ant-corruption.html And the ethology article on wikipedia thinks that the revengeful behavior is only observed in humans, but a famous example is vampire bats. Watch “Planet Earth” If they don’t get food during the night, they’ll die. So if one comes pack without food, he’ll ask someone to share, if no one shares he dies. However the bat who didn’t share is observed by others, and if he isn’t able to get food on a subsequent night, no one will share with him. And i’ve posted on him before but Martin Nowak does good work with mathematical biology. Evolution of altruism, stuff like that. Also I don’t think all hunter forager cultures would have the generalized reciprocity.

            And as for problems extrapolating this out to Evolutionary Psychology, and biologists criticism’s of psychologists. http://somatopsychic.blogspot.com/2009/02/reading-list-evolutionary-psychology.html

          • Thanks edeast! Interesting stuff. It’s not clear to me if the ants aware of how reproduction works and are thus making fertilization decisions on that basis, or if its strictly instinctive behaviour that has a pattern only due to evolutionary pressures. The distinction is important, because it’s not cheating if the individual doesn’t knowingly seek an advantage at the expense of others.

            The second link outlines the concerns a lot of us have with studies like the one above.

            Thanks again!

          • On second thought, it could just be biologists’ not understanding psychologist’s methods.

          • “It’s not clear to me if the ants aware of how reproduction works and are thus making fertilization decisions on that basis, or if its strictly instinctive behaviour that has a pattern only due to evolutionary pressures. The distinction is important, because it’s not cheating if the individual doesn’t knowingly seek an advantage at the expense of others.”

            Ignorance is bliss, if unknowingly seeking an advantage is an absolution. Cheating, morality, things like that are value statements, imposed from who knows where, I guess that is what these researchers are trying to find out; whether there is an objective source or subjective source. But I would argue that evolutionary pressures would affect a Kantian rational creatures’ behavior as well, not just at the instinctual level.

  3. I think you are focusing too much on the specific case, rather than the broader implications.

    What is interesting about this article is that it suggests (as for instance, John Haidt’s work also suggests) that morality has a lot to do with our “wretch” reflex. Haidt found that conservatives were more likely to have the “eww… unclean!” reaction to things than liberals.

    This represents a critique of any notion of objective morality – if we look deep down are they merely providing ad hoc reasons for their disgust. It provides the causal mechanism by which morals work. It also gives us some means of predicting say, what kind of people will cheat, or disapprove of cheaters. It also gives insight into how informal sanctioning mechanisms might work – even without a law about cheating. One could imagine that humans might be conditioned to have the same reaction to other harmful behavior.

    • “One could imagine that humans might be conditioned to have the same reaction to other harmful behavior.”

      Harmful behaviour with respect to themselves. It really only is with Christianity that we started viewing harmful behaviour towards third parties as objectively bad.

      • “Harmful behaviour with respect to themselves. It really only is with Christianity that we started viewing harmful behaviour towards third parties as objectively bad.”

        I am talking about socially harmful behavior. You are adopting an atomistic perspective – but to survive, human collectivities, like all animals (for instance you may have noticed that different animals have staked various positions on that spectrum too – eg. ants vs. cockroaches vs. spiders) have needed some mix of collectivism and individualism. That is essentially Margolis’ answer to rat choice – what works best for individuals does not always work best for the whole, so you need some degree of altruism for a particular collectivity to survive in competition with others. Insofar as cheating is bad for the community, some combination of shaming mechanisms and centuries of teaching have made humans react that way.

        I think you rely excessively on an individualist foundation here. People insofar as they are members of communities, particularly the small communities of yore bolstered by informal shaming mechanisms, etc. view harm to the community as harm to themselves. Having people that think that way is useful in curbing collective action problems. eg. if you have a problem where land is owned collectively, such that each individual has an incentive to overgraze the land (Hardin’s tragedy of the commons), a norm against over-grazing can be effective. The widespread nature of these norms suggests that they much predate Christianity.

        On the topic of collectivist views of humanity, I would recommend this essay by Haidt. He starts with the question of why people become Republicans (as a liberal atheist himself). He found his anthropological work in India radically changed his perspective, as he came to realize that the conservative values (he really means socially conservative) of Indians are rooted in a view of society where the family, not the individual is the basic unit of analysis. Essentially conservatives view humans and institutions as being interdependent. They fear change because, as with many complex systems, radical change can often lead to collapse.*

        *If you want an example… the 1960’s welfare state was based on an ever-expanding population, with fewer old people than young people. Birth control and new medical techniques made the 1960’s welfare state impossible to sustain. They may still be good things in and of themselves, but conservatives chafe at the idea of simply looking at things in terms of individual rights, when doing so has collective consequences. So with gay marriage, they aren’t so much concerned that gay people might have sex, but rather that the definition and social understanding of marriage is changing to something that clearly will and is having social dislocations. That makes it hard for them to debate public policy – because they are often using a political forum to sell a moral point of view.

        • I think that we are arguing at cross purposes. I certainly agree moralities arise from a sense of group solidarity, i.e. what is harmful to the group is “wrong.” But what happened with Christianity, for the first time in the West apart from a few philosophers, is that “the group” was extended to include all humanity; consequently, no individual was supposed to do harm to another, all being (theoretically) members of the same group. So it appears to be individualistic only because no other group is allowed for in moral terms. Of course it didn’t always work out that way, but that is the origin of our notion that morality is absolute, i.e. individualistic.

          Historically, this could only have happened in the peaceful Roman Empire, because before that period, as you say, groups were continuously colliding and fighting for survival: thus they would have one morality for dealing with members of the group and another for dealing with outsiders. And naturally there was a range of “outsiders,” especially once civilisation appeared and we got divided up into castes: a Norman knight would feel he was closer to a Provencal knight, group-wise, than he was with his serfs, hence one morality for dealing with other nobles (chivalry) and another for dealing with peasants (very open-ended).

          We should beware, therefore, of importing our Christianity-derived self-identification with the whole of humanity, our ideas of absolute (generalised, individualistic) morality, with our Stone Age ancestors and our more remote mammal ancestors. “Thou shalt not kill,” for instance, is pretty standard fare today but would not have made sense to them: their version was “Thou shalt not kill within thy own group.” Ditto for cheating etc.

          • The Christian point reminds me of , (I’ll try and find it), one of Iran’s leaders saying the human rights, are just secularized Christianity.

          • Ah, that’s interesting about the Iranian statement. I’d tend to agree with him! Though I’m a bit surprised that he wouldn’t say the same thing about Islam, which likewise (I’d have thought) lays claim to fairly universal applicability. Perhaps not in Iran, which, unlike Egypt, Syria, Turkey, and North Africa, was Zoroastrian (or Manichaean?) when it converted.

  4. Also, couldn’t this study be summarized with a more simple explanation? “Negative feelings seem to provoke similar reflexive facial expressions, regardless of the trigger.” Seems to me that’s all they have evidence for as it stands.

    I haven’t seen this particular study, but I’m rarely surprised to learn that they are based on ridiculously small and non-representative samples, often drawn from the undergraduate student population where they teach. Which is all well and good for a minor study that provides us with some amusement, but is a whole different problem when we’re trying to make statements about all humans, and our proto-human ancestors.

    At least the ethnographic data I was referencing above is reasonably cross-cultural in nature, and even then I’m very cautious about extraopolating too much from it. These sorts of studies – at least by the time they hit the mainstream media – seem to throw such caution out the window.