Buridan’s ass

philosophy and logic

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June 22, 2026

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Buridan's ass is a philosophical dilemma illustrating a problem of choice. It describes a hypothetical situation where an equally hungry and thirsty donkey is placed precisely between two identical bales of hay and two identical troughs of water. Because there is no reason for the donkey to choose one option over the other, the donkey is unable to make a choice and would theoretically starve or die of thirst.

This thought experiment, though often attributed to Jean Buridan, a 14th-century philosopher, was not explicitly stated by him in the form of an ass. Buridan discussed a similar problem involving a dog choosing between two equal portions of food, exploring how an agent makes a choice when faced with symmetrical options. The dilemma highlights issues of free will, determinism, and the nature of decision-making when faced with equally appealing alternatives.12

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Jean Buridan
…by the celebrated allegory of “Buridan’s ass,” though the animal mentioned in Buridan’s commentary on Aristotle’s De caelo (“On the Heavens”) is actually a dog, not an ass. His discussion centres on the method by which the dog chooses between two equal amounts of food placed before him. Discerning both…
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…by the celebrated allegory of “Buridan’s ass,” though the animal mentioned in Buridan’s commentary on Aristotle’s De caelo (“On the Heavens”) is actually a dog, not an ass. His discussion centres on the method by which the dog chooses between two equal amounts of food placed before him. Discerning both…
Read More