In a rational choice model, cheating and stealing can become rational when people have less to lose from not cheating and stealing than they risk by cheating and stealing. And if they don’t trust one another, they are even more likely to cheat and steal. The more unequal a society is, the more likely people will fall below the threshold where they judge they have nothing to lose, and the less trust there will be between and within social classes.

 If your current resources are above the threshold, then, under the assumptions we make, it is not worth stealing. Instead, you should cooperate as long as you judge that the others around you are likely to do so too, and just work alone otherwise. If your resources are around or below the threshold, however, then, under our assumptions, you should pretty much always steal. Even if it makes you worse off on average.

This is a pretty remarkable result: why would it be so? The important thing to appreciate is that with our threshold, we have introduced a sharp non-linearity in the fitness function, or utility function, that is assumed to be driving decisions. Once you fall down below that threshold, your prospects are really dramatically worse, and you need to get back up immediately. This makes stealing a worthwhile risk. If it happens to succeed, it’s the only action with a big enough quick win to leap you back over the threshold in one bound. If, as is likely, it fails, you are scarcely worse off in the long run: your prospects were dire anyway, and they can’t get much direr. So the riskiness of stealing – it sometimes you gives you a big positive outcome and sometimes a big negative one – becomes a thing you should seek rather than avoid…

So if making sentences tougher does not solve the problems of crime in high-inequality populations, according to the model, is there anything that does? Well, yes: and readers of this blog may not be surprised to hear me mention it. Redistribution. If people who are facing desperation can expect their fortunes to improve by other means, such as redistributive action, then they don’t need to employ such desperate means as stealing. They will get back up there anyway. Our model shows that a shuffling of resources so that the worst off are lifted up and the top end is brought down can dramatically reduce stealing, and hence increase trust. (In an early version of this work, we simulated the effects of a scenario we named ‘Corbyn victory’: remember then?).

Daniel Nettle

Well, you can redistribute, or there are other options. The highest social classes could maintain the social order through sheer force. Or they could try to achieve the same ends through ideology and propaganda that convince the lower classes the social order is natural or desirable, or they can try to use ideology and propaganda to divide the lower classes and turn them on each other. The guy on the second rung from the bottom may very well be willing to kick the guy on the bottom rung in the teeth to keep him from climbing, and thank the people higher up for the opportunity even while they are shitting on his head. Which of these options sounds good to you probably depends on which rung of the ladder you happen to be standing on, and the rung you happen to be standing on is probably within a couple rungs of the one you were born on, in most cases.