Wittgenstein and the concept of rationality

Countertenor Philippe Jaroussky and his ensemble Atarserse in the TivoliVredenburg concert hall

In my last blog we have seen that we can act in a rational way although what we do is not necessarily rational according to the utility theory in economics. But what is rationality? On the Internet, you can find many definitions, some better, some worse, but let me say it this way: Actions are rational if they contribute to our present purposes. This is rather vague and I could add yet a phrase like “in the best way”, but I think that the essence of what I mean is clear. So, if I want to go from my house to the TivoliVredenburg concert hall in Utrecht, I can take the train, my car or my bike. Each of these means is rational in view of the purpose of going there. Moreover I can add some criteria, like “in the cheapest way”, “as quick as possible”, “conveniently” or what more, and then I can make my definite choice. So in order to make our choices, we often have to add secondary purposes. Seen that way, it is not obvious that our purposes are economic in the first place. It’s quite well possible that our choices are not rational in an economic sense, although they are rational of a kind. It’s a thing that economists – and politicians as well – often forget and it’s why Daniel Kahneman, by showing this, received the Nobel Prize. I can say it also in this manner: Rationality is not an intrinsic property of our actions. It depends on the context.

Although Wittgenstein didn’t develop an explicit theory of rationality, just that rationality is context-dependent, becomes clear from his work, especially if we look at his idea of language game. In his Philosophical Investigations (PI) he writes: “Consider for example the proceedings that we call ‘games’. I mean board-games, card-games, ball-games, Olympic games, and so on. What is common to them all? ... [I]f you look at them you will not see something that is common to all, but similarities, relationships, and a whole series of them at that. ... Look for example at board-games, with their multifarious relationships. Now pass to card-games; here you find many correspondences with the first group, but many common I features drop out, and others appear. When we pass next to ballgames, much that is common is retained, but much is lost.—Are they all ‘amusing’? Compare chess with noughts and crosses. Or is there always winning and losing, or competition between players? Think of patience. In ball games there is winning and losing; but when a child throws his ball at the wall and catches it again, this feature has disappeared. [Etc.] [T]he result of this examination is: we see a complicated network of similarities overlapping and criss-crossing: sometimes overall similarities, sometimes similarities of detail.” (PI 66). In my words: A game is a certain game because of a set of rules that apply only to this game. A specific rule is out of place if applied in another game, unless it happens that it explicitly belongs to that other game as well and fits in its set of rules. But usually this is mere chance. Usually a rule is only valid in the context of other rules with which it constitutes a certain game (like football, bridge, chess, bicycle race ...). Nonetheless we bring all these different games together under one heading: “games”. It is because we think that they have something in common and that they are similar in relevant respects. Here Wittgenstein says: “I can think of no better expression to characterize these similarities than ‘family resemblances’; for the various resemblances between members of a family: build, features, colour of eyes, gait, temperament, etc. etc. overlap and criss-cross in the same way.— And I shall say: ‘games’ form a family.” (PI 67)

What has this all to do with rationality? We have seen that we often talk of “game” but that we can fill in this concept in different ways. It is the context constituted by the specific rules that make up a specific game. It’s the same with “rationality”. Rationality is not a univocal concept that can be filled in in only one way: by money values. There are also other ways to express the idea: positive or negative feelings, for instance. Or speed or convenience. Nevertheless all these interpretations have enough in common to use one word for it: Rationality. But this doesn’t mean that what is rational in one context need also be so in another one, just as we don’t say that a cyclist has scored a goal when he finishes first.