A question was asked here relatively recently about the ability of human's to come up with truly random numbers, and (in my opinion) one can meaningfully ask that same question regarding almost any system. My question is directed towards the deterministic opinion (though I know not all those who adhere to determinism would agree) that true randomness is not possible.

Considering the thought experiment known as Buridan's Ass, in which a perfectly rational ass (donkey) would starve to death when presented with two piles of hay that are exactly equidistant form the ass and perfectly identical to each other, because it cannot rationally choose one over the other. However, the 'rational' decision (for the ass with a sense of self-preservation, etc) is not to starve to death, but to pick any stack of hay at random. In a human equivalent, that human would perhaps flip a coin.

However, what if there was no coin to flip, or similar mechanism of deciding between two equally beneficial choices arbitrarily, when the alternative to choosing is a highly undesirable outcome? How, indeed, would the rational person save himself from starvation?

1 Answer 1


I will answer in what seems like either a serious jest or dialectical irony: by using a better definition of rationality.

Yes, a certain level of thinking would get you stuck unable to pick between two equally desirable outcomes and thus winding up worse than either. But this seems to be a thoroughly impoverished definition of rationality. You demonstrate that clearly in your own objection -- this rationality seems unable to incorporate the negative consequences of not choosing. This if there is any source of randomness that can help the ass pick, it should use this to decide the meaningless choice.

Now, you can keep the thought experiment alive by eliminating any source of randomness to help the ass. But then it seems like a robust form of rationality in such a world would devise a rule that handles these situations: "given two equally arbitrary options and the necessity of picking one or the other, go left" [or some such rule]. (This seems to me to be a feature of how we understand the conditional with a false antecedent -- we need to pick something if we want to keep our logic bivalent).

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .