I think you know the situation: Two children are playing around as children often do. Let’s say that they are a bit boxing or something like that. One gives a blow to the other. “Don’t beat me that hard”, the other says and strikes back. Then the first one says: “I dont beat hard. You do!” And before you know it, they are really fighting. We call this escalation. Why did this happen?
In an article by Suparna Choudhury and Sarah-Jayne Blakemore I found an interesting explanation of this phenomenon, which they derived from a study by S.S. Shergill et al.: “... just as happens when we try to tickle ourselves, the brain predicts the sensory consequences of the self-generated force and then reduces the sensory feedback. Since the forward model can only predict the outcome of our own actions and not of those of someone else, sensations that are externally caused are enhanced relative to self-produced sensations. As a result, if you were to deliver a vengeful punch to match the force of your opponent’s blow, it is likely that you would overestimate the strength of the opponent’s punch and strike back harder”. (source: see below) In short: We tend to underestimate the force of our own actions (blows), because the sensations related to them are attenuated, while we don’t correctly judge the force when dealing a blow to another person. Even if the other person wants to strike back with the same force, his blow will be harder than the one received. The result is escalation.
I think that this is a general phenomenon: We often underestimate the effects of what we do. We underestimate the way we talk negatively about other people or even hurt them purposively, while we overestimate it when other people talk bad about us or hurt us with their words. When we feel guilty if other people accuse us of having done something bad, we think that what we did is not as bad as when we see a third person doing the same.
However, the phenomenon is wider. You see it everywhere where people maintain relations to others, especially in politics and in war. In war, the victims on your side count more than the same number of victims on the side of your enemy. “Our revenge will be thousandfold”. “One victim on our side means ten on theirs”. Who doesn’t know words like these? The harm done to your side looks bigger than the harm on the other side done by you, so by way of revenge the harm is increased when hitting back. Again: The result is escalation. Within societies the restraints that escalation really will take place are much bigger than in international affairs, although happily even there the restraints on conflicts are growing. The essence of the problem is, of course, a kind of ego-centration, together with your physical setup. The upshot is: Behave yourself and put yourself in the shoes of the other.Source: Suparna Choudhury and Sarah-Jayne Blakemore, “Intentions, Actions, and the Self”, in: Susan Pockett, et al., Does consciousness cause behavior? Cambridge, Mass. etc.: MIT Press, 2006; pp. 41-42.