Game theory — theory with little substantive content

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Lars Pålsson Syll
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from Lars Syll

I don’t see that we are even entitled to assume that reality accords to some model that humans are able to envisage … To say that Pandora knows what decision model she is facing can therefore be taken as meaning no more than that she is committed to proceeding as though her model were true …

The price of abandoning psychology for revealed-preference theory is therefore high. We have to give up any pretension to be offering a causal explanation of Pandora’s choice behavior in favour of an account that is merely a description of the choice behavior of someone who chooses consistently. Our reward [sic!] is that we end up with a theory that is hard to criticise because it has little substantive content.

Back in 1991, when yours truly earned his first PhD​ with a dissertation on decision-making and rationality in social choice theory and game theory, I concluded that “repeatedly it seems as though mathematical tractability and elegance — rather than realism and relevance — have been the most applied guidelines for the behavioural assumptions being made. On a political and social level, ​it is doubtful if the methodological individualism, ahistoricity and formalism those guidelines imply are especially valid for explaining real-world decision-making.”

This, of course, was like swearing in church. My mainstream colleagues were — to say the least — not exactly überjoyed.

For certain specific, local problems, game theory is a very nice way of thinking about how people might try to solve them, but as soon as you are dealing with a general problem like an economy or a market, I think it is difficult to believe that there is full strategic interaction going on. It is just asking too much of people. Game theory imposes a huge amount of abstract reasoning on the part of people …

That is why I think game theory, as an approach to large scale interaction, is probably not the right way to go.

Alan Kirman

Half a century ago there were widespread hopes game theory would provide a unified theory of social science. Today it has become obvious those hopes did not materialize. This ought to come as no surprise. Reductionist and atomistic models of social interaction — such as those mainstream economics and game theory are founded on — will never deliver sustainable building blocks for a realist and relevant social science. That is also — as yours truly argues here — the reason why game theory never will be anything but a footnote in the history of social science.

Heavy use of formalism and mathematics easily foster the view that a theory is scientific. But although game theory may produce ‘absolute truths’ in imaginary model worlds, in the real world the game theoretic models are nothing but fables. Fables much reminiscent of the models used in logic, but also like them, delivering very little of value for social sciences trying to explain and understand real-life phenomena. The games that game theory portrays are model constructs, models without significant predictive capacity simply because they do not describe an always much more complex and uncertain reality …

Although some economists consider it useful to apply game theory and use game theoretical definitions, axioms, and theorems and (try to) test if real-world phenomena ‘satisfy’ the axioms and the inferences made from them, we have argued that that view is without warrant. When confronted with the real world we can (hopefully) judge if game theory really tells us if things are as postulated. The final court of appeal for models is the real world, and as long as no convincing justification is put forward for how the inferential bridging de facto is made, model building is little more than hand-waving that give us rather little warrant for making inductive inferences from the model world to the real world.

The real challenge in social science is to accept uncertainty and still try to explain why different kinds of transactions and social interactions take place. Simply conjuring problems away by assuming patently unreal things and treating uncertainty as if it was possible to reduce to stochastic risk, is like playing tennis with the net down. That is not the kind of game that scientists working on constructing a relevant and realist science want to play.