Positive sum-bias

People often talk about zero sum-bias - the tendency to believe that positive sum-situations are zero sum. In other words, zero sum-bias is to believe that one person’s gain is another person’s loss, even when that’s not the case. Zero sum-bias is said to lead to hostility to cooperation and trade, to protectionist policies, to a neglect of economic growth, and so on. It’s often argued that it’s a pervasive impediment to peace and progress, that we need to overcome.

But while zero sum-bias definitely exists, there are also many examples of positive sum-bias: the belief that zero sum-situations are positive sum. One example is grade inflation. At first glance, giving a student a higher grade might seem positive sum: it helps one student without harming the others. But in reality, it does harm all the other students, whose chances of getting good jobs or degrees are reduced when a competitor gets higher grades. The harm to each of the other students is so small as to be nearly imperceptible, but together these harms add up to be roughly equal to the gain that the student who receives a higher grade makes.

Relatedly, opportunity cost neglect in the context of altruistic actions can be seen as a form of positive sum-bias. Giving money to one cause has an opportunity cost: the “cost” of not being able to give the money elsewhere. When you neglect the opportunity cost of giving to a particular cause, you fail to see that that means that you can’t give the money elsewhere. So choosing to give to A rather than to B appears positive sum, even though it’s zero sum: more money to A entails less to B.

Of course, opportunity cost neglect is a much-discussed topic, as is biases relating to grade inflation. But they’re rarely discussed in the context of zero sum-bias, as examples of the opposite tendency. In discussions about zero sum-bias, it’s usually implied that people have a general tendency towards zero sum-thinking, and that the solution is that we should be more inclined to see situations as positive sum across the board. But grade inflation and opportunity cost neglect demonstrates that there are situations where we should be more inclined to see situations as zero sum. In these situations, we fail to notice that some people’s gain leads to other people’s losses - and we should become more sensitive to that.

Hence the solution isn’t just to dial down our tendency towards zero sum-thinking in general, but to become better attuned to the logic of each particular situation. Sometimes we do indeed mistake a positive sum-situation for a zero sum-situation, but at other times, it’s the other way around. Indeed, that’s exactly what we should expect, on priors. It would have been surprising if all of our mistakes were in the same direction.

Relatedly, while making people more inclined to see situations as positive sum may sometimes make them more cooperative, there is a risk that one might overrate that factor. Incentives, norms, and institutions that are conducive to cooperation are often more important. And to set up the right incentives, norms, and institutions, we first need to have a realistic picture of the logic of each particular situation. And that will sometimes mean that we need to shift our beliefs in a zero sum-direction. So what we need isn’t necessarily one big push towards less zero sum-thinking, but rather a thousand small adjustments of our thinking and our social structures, that pay careful attention to the details of each situation. That’s much harder work.

It seems that we have a meta-bias: a bias towards focusing more on zero sum-bias than positive sum-bias. Why might that be? One reason could be that the message that we should just become better at observing our common interests is quite emotionally and politically appealing. By contrast, the notion that we should become better at observing how people are harmed by seemingly innocent decisions is arguably less appealing to many.