Q&A: Buridan’s Ass and Determinism
Buridan’s Ass and Determinism
Question
I heard you present the question of Buridan’s ass in a lecture on determinism.
The question puts a person in place of the donkey and asks: if a person were standing at equal distances from food, would he die of hunger?
I wanted to add that for the situation to exist under perfect conditions, we need to assume not only that the person is at equal distances from the food, but that his entire life took place with no difference between left and right. For example, a person who, as a child, was told that it is always better to go right might choose the right side even when the distance is equal, and that would be the rational deterministic choice for him.
If so, we need to imagine a situation in which a person has lived a completely symmetrical life with respect to food all his life, both externally and internally. That is, his brain activity is also completely symmetrical—he is neither right- nor left-dominant—and throughout his life all his experiences were equal and symmetrical. This would mean a reality and a world in which even the laws of nature are always symmetrical, and everything a person experiences is symmetrical.
This is a completely fictional reality that is hard even to imagine, but only in such a reality can the thought experiment be carried out.
In such a situation, it is no longer so hard to imagine that the person might not be able to choose a side and would die of hunger, and perhaps he would not even be able to move his legs, because any movement would be the first symmetry-breaking event in a world with symmetrical laws.
Answer
First of all, this is a thought experiment. Your scenario changes nothing with respect to my argument. But beyond that, there is no need at all to assume anything about his biography. It is enough to assume that his brain—and indeed his whole being—is now in a symmetrical state. Even if he went through many adventures that balanced each other out and brought his brain to a state of symmetry between right and left, that is enough.