The creature who, placed midway between two identical bales of hay, starved to death, since there was no reason for moving one way rather than the other. The ass is not referred to in the Sophismata of Buridan, but was probably an example used to refute him, since he held that choice is always delayed until reason has decided in favour of one course of action against another. A similar example of a dog is found in Aristotle, De Caelo (295 b 32).