People are social creatures. This is a statement that surprises no one, seeming trivial to the same degree it is widely recognized (which is to say, "very"). That many people will recognize such a statement in the abstract and nod their head in agreement when they hear it does not mean they will always apply it to their thinking in particular cases, though. Let's start with a context in which people will readily apply this idea to their thinking about the world: a video in which pairs of friends watch porn together while being filmed by others who have the intention to put the video online for view by (at the time of writing) about 5,700,000 people worldwide. The video is designed to get people's reactions to an awkward situation, but what precisely is it about that situation which causes the awkward reactions? As many of you will no doubt agree, I suspect that answer has to do with the aforementioned point that people are social creatures. Because we are social creatures, others in our environment will be relatively inclined (or disinclined) from associating with us contingent on, among other things, our preferences. If some preferences make us seem like a bad associate to others - such as, say, our preferences concerning what kind of arouses us, or our interest in pornography more generally - we might try to conceal those preferences from public view. As people are trying to conceal their preferences, we likely observe a different pattern of reactions to - and searches for - pornography in the linked video, compared to what we might expect if those actors were in the comfort and privacy of their own home.

Source: Flickr/persand

Basically, we would be wrong to think we get a good sense for these people's pornography preferences from their viewing habits in the video, as people's behavior will not necessarily match their desires. With that in mind, we can turn to a rather social human behavior: . Now, punishment might not be the first example of social behavior that pops into people's heads when they think about social things, but make no mistake about it; punishment is quite social. A healthy degree of human gossip centers around what we believe ought to be and not be punished; a fact which, much to my dismay, seems to take up a majority of my social media feeds at times. More gossip still concerns details of who was punished, how much they were punished, why they were punished, and, sometimes, this information will lead to other people joining in the punishment themselves or trying to defend someone else from it. From this analysis, we can conclude a few things, chief among which are that, (a) some portion of our value as an associate to others (what I would call our association value) will be determined by the perception of our punishment preferences, and (b) punishment can be made most or less costly, contingent on the degree of social support our punishment receives from others.

This large social component of punishment means that observing the results of people's punishment decisions does not necessarily inform you as to their preferences for punishment; sometimes people might punish others more or less than they would prefer to, were it not for these public variables being a factor. With that in mind, I wanted to review two pieces of research to see what we can learn about human punishment preferences from people's behavior. The first piece claims that human punishment mechanisms have - to some extent - evolved to seek equal outcomes between the punisher and the target of their punishment. In short, if someone does some harm to you, you will only desire to punish them to the extent that it will make you two "even" again. An eye for an eye, as the saying goes; not an eye for a head. The second piece makes a much different claim: that human punishment mechanisms are not designed for fairness at all, seeking instead to inflict large costs on others who harm you, so as to deter future exploitation. Though both of these papers do not assess punishment in a social context, I think they have something to tell us about that all the same. Before getting to that point, though, let's start by considering the research in question.

The first of these papers is from Bone & Raihani (2015). Without getting too bogged down in the details, the general methods of the paper go as follows: two players enter into a game together. Player A begins the game with $1.10 while player B begins with a payment ranging from $0.60 to also $1.10. Player B is then given a chance to "steal" some of player A's money for himself. The important part about this stealing is that it would either leave player B (a) still worse off than A, (b) with an equal payment to A, or (c) with a better payment than A. After the stealing phase, player A has the chance to respond by "punishing" player B. This punishment was either efficient - where for each cent player A spent, player B would lose three - or inefficient - where for each cent player A spent, player B would only lose one. The results of this study turned up the following findings of interest: first, player As who were stolen from tended to punish the player Bs more, relative to when the As were not stolen from. Second, player As who had access to the more efficient punishment option tended to spend more on punishment than those who had access to the less efficient option. Third, those player As who had access to the efficient punishment option also punished player Bs more in cases where B ended up better off than them. Finally, when participants in that former case were punishing the player Bs, the most common amount of punishment they enacted was the amount which would leave both player A and B with the same payment. From these findings, Bone & Raihani (2015) conclude that:

Although many of our results support the idea that punishment was motivated primarily by a desire for revenge, we report two findings that support the hypothesis that punishment is motivated by a desire for equality (with an associated fitness-leveling function...)

In other words, the authors believe they have observed the output of two distinct preferences: one for punishing those who harm you (revenge), and one for creating equality (fitness leveling). But were people really that concerned with "being even" with their agent of harm? I take issue with that claim, and I don't believe we can conclude that from the data.

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To see why I take issue with that claim, I want to consider an earlier paper by Houser & Xiao (2010). This study involves a slightly different setup. Again, two players are involved in a game: player A begins the game by receiving $8. Player A could then transfer some amount of that money (either $0, $2, $4, $6, or $8) to player B, and then keep whatever remained for himself (another condition existed in which this transfer amount was randomly determined). Following that transfer, both players received $2. Finally, player B was given the following option: to pay $1 for the option to reduce player A's payment by as much as they wanted. The results showed the following pattern: first, when the allocations were random, player B rarely punished at all (under 20%) and, when they did punish, they tended to punish the other player irrespective of inequality. That is they were equally as likely to deduct at all, no matter the monetary difference, and the amount they deducted did not appear to aimed at achieving equality. By contrast, of the player Bs that received $0 or $2 intentionally, 54% opted to punish player A and, when they did punish, were most likely to deduct so much from player A that they ended up better off than him (that outcome obtained between 66-73% of the time). When given free reign over the desired punishment amount, then, punishers did not appear to be seeking equality as an outcome. This finding, the authors conclude, is inconsistent with the idea that people are motivated to achieve equality per se.

What both of these studies do, then, is vary the cost of punishment. In the first, punishment is either inefficient (1-to-1 ratio) or quite efficient (3-to-1 ratio); in the second, punishment is unrestricted in its efficiency (X-to-1 ratio). In all cases, as punishment becomes more efficient and less costly, we observe people engaging in more of it. What we learn about people's preferences for punishment, then, is that they seems to be based, in some part, on how costly punishment is to enact. With those results, I can now turn to the matter of what they tell us about punishment in a social context. As I mentioned before, the costs of engaging punishment can be augmented or reduced to the extent that other people join in your disputes. If your course of punishment is widely supported by others, this means its easier to enact it; if your punishment is opposed by others, not only is it costlier to enact, but you might in turn get punished for engaging in your excessive punishment. This idea is fairly easy to wrap one's mind around: stealing a piece of candy from a corner store does not usually warrant the death penalty, and people would likely oppose (or attack) the store owner or some government agency if they attempted to hand down such a draconian punishment for the offense.

Now many of you might be thinking that third parties were not present in the studies I mentioned, so it would make no sense for people to be thinking about how these non-existent third parties might feel about their punishment decisions. Such an , I feel, would be a mistake. This brings me back to the matter of pornography briefly. As I've written before, people's minds tend to generate physiological arousal to pornography despite there being no current adaptive reason for that arousal. Instead, our minds - or, more precisely, specific cognitive modules - attend to particular proximate cues when generating arousal that historically correlated with opportunities to increase our genetic fitness. In modern environments, where that link between cue and fitness benefit is broken by digital media providing similar proximate cues, the result in maladaptive outputs: people get aroused by an image, which makes about as much adaptive sense as getting aroused by one's chair.

The same logic can likely be applied to punishment here as well, I feel: the cognitive modules in our mind responsible for punishment decisions evolved in a world of social punishment. Not only would your punishment decisions become known to others, but those others might join in the conflict on your side or opposing you. As such, proximate cues that historically correlated with the degree of third party support are likely still being utilized by our brains in these modern experimental contexts where that link is being intentionally broken and interactions are anonymous and dyadic. What is likely being observed in these studies, then, is not an aversion to inequality as much as an aversion to the costs of punishment or, more specifically, the estimated social and personal costs of engaging in punishment in a world that other people exist in.

Source: Flickr/BlPlN

When punishment is rather cheap to enact for the individual in question - as it was in Houser & Xiao (2010) - the social factor probably plays less of a role in determining the amount of punishment enacted. You can think of that condition as one in which a king is punishing a subject who stole from him: while the king is still sensitive to the social costs of punishment (punish too harshly and the rabble will rise up and crush you...probably), he is free to punish someone who wronged him to a much greater degree than your average peasant on the street. By contrast, in Bone & Raihani (2015), the punisher is substantially less powerful and, accordingly, more interested in the (estimated) social support factors. You can think of those conditions as ones in which a knight or a peasant is trying to punish another peasant. This could well yield inequality-seeking punishment in the former study and equality-seeking punishment in the latter, as different groups require different levels of social support, and so scale their punishment accordingly. Now the matter of why third parties might be interested in inequality between the disputants is a different matter entirely, but recognition of the existence of that factor is important for understanding why inequality matters to second parties at all.

References: Bone, J. & Raihani, N. (2015). Human punishment is motivated both by a desire for revenge and a desire for equality. Evolution & Human Behavior, 36, 323-330.

Houser, D., & Xiao, E. (2010). Inequality-seeking punishment. Economics Letters, 109, 20-23.