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[QUICK THREAD: BURIDAN'S ASS]
1/28
An old French proverb goes, on ne fait pas boire un âne qui n'a pas soif. Translated to English, one does not make a donkey drink if it isn't thirsty.
But what if the donkey WERE thirsty? And also hungry? Equally?
1/28
An old French proverb goes, on ne fait pas boire un âne qui n'a pas soif. Translated to English, one does not make a donkey drink if it isn't thirsty.
But what if the donkey WERE thirsty? And also hungry? Equally?
2/28
In 350 BC, an influential Athenian thinker wrote Περὶ οὐρανοῦ (On the Heavens), a landmark cosmological treatise on his understanding of how the universe worked. His name was Aristotle.
Those days, the Sun went around the Earth, as did other planets.
In 350 BC, an influential Athenian thinker wrote Περὶ οὐρανοῦ (On the Heavens), a landmark cosmological treatise on his understanding of how the universe worked. His name was Aristotle.
Those days, the Sun went around the Earth, as did other planets.
3/28
The Earth hadn't been flat for at least a hundred years at the time. But heliocentrism, the idea that the Earth and other planets went around the Sun, was still in its infancy. Proponents of this thought were largely fringe.
The Earth hadn't been flat for at least a hundred years at the time. But heliocentrism, the idea that the Earth and other planets went around the Sun, was still in its infancy. Proponents of this thought were largely fringe.
4/28
Ironically, the Earth being spherical was given as the most compelling argument in favor of geocentrism. Sophists, a community of itinerant philosophers following the pre-Socratic school of thought, were the biggest advocates of the geocentric cosmology.
Ironically, the Earth being spherical was given as the most compelling argument in favor of geocentrism. Sophists, a community of itinerant philosophers following the pre-Socratic school of thought, were the biggest advocates of the geocentric cosmology.
5/28
Since the Earth was spherical, sophists argued, it must experience equal forces on all sides. And equal forces on all sides meant all of them canceled each other out, which further meant the Earth couldn't be in motion.
Makes sense, right?
Not to one individual.
Since the Earth was spherical, sophists argued, it must experience equal forces on all sides. And equal forces on all sides meant all of them canceled each other out, which further meant the Earth couldn't be in motion.
Makes sense, right?
Not to one individual.
6/28
That individual was Aristotle. He had an entire bouquet of resentments against the sophists, this was one of them. So convinced he was of the ridiculousness of geocentrism that he brought it up in his treatise as a prominent subject of discussion.
That individual was Aristotle. He had an entire bouquet of resentments against the sophists, this was one of them. So convinced he was of the ridiculousness of geocentrism that he brought it up in his treatise as a prominent subject of discussion.
7/28
To illustrate his point, Aristotle used an analogy:
"A man, being just as hungry as thirsty, and placed in between food and drink, must necessarily remain where he is and starve to death."
Hunger and thirst are analogous to two opposing forces here.
To illustrate his point, Aristotle used an analogy:
"A man, being just as hungry as thirsty, and placed in between food and drink, must necessarily remain where he is and starve to death."
Hunger and thirst are analogous to two opposing forces here.
8/28
Of course, nobody would starve to death or die of thirst when put in that hypothetical situation. One would always pick one or the other, even if randomly. Same way, Aristotle posited, equal forces on all sides don't necessarily mean the Earth must stand still.
Of course, nobody would starve to death or die of thirst when put in that hypothetical situation. One would always pick one or the other, even if randomly. Same way, Aristotle posited, equal forces on all sides don't necessarily mean the Earth must stand still.
9/28
Aristotle's analogy may not make mathematical sense, but it did find at least some takers during his time. Of course, heliocentrism wouldn't go mainstream until Copernicus, some 1,700 years later.
This analogy remained cosmological in the beginning.
Aristotle's analogy may not make mathematical sense, but it did find at least some takers during his time. Of course, heliocentrism wouldn't go mainstream until Copernicus, some 1,700 years later.
This analogy remained cosmological in the beginning.
10/28
Then some 1,400 years down the line, a Persian thinker got hold of this analogy. He found it so incoherent and lacking in reason, he extrapolated it well outside cosmology and applied it to the question of determinism.
His name was Al-Ghazâlî.
Then some 1,400 years down the line, a Persian thinker got hold of this analogy. He found it so incoherent and lacking in reason, he extrapolated it well outside cosmology and applied it to the question of determinism.
His name was Al-Ghazâlî.
11/28
Abū Ḥāmid Muḥammad ibn Muḥammad aṭ-Ṭūsiyy al-Ġazālīy, Latinized as Algazelus, was an influential theologian and political thinker from the city of Tus in the Seljuq Empire.
Al-Ghazâlî was one of the biggest critics of Aristotelian sciences of all times.
Abū Ḥāmid Muḥammad ibn Muḥammad aṭ-Ṭūsiyy al-Ġazālīy, Latinized as Algazelus, was an influential theologian and political thinker from the city of Tus in the Seljuq Empire.
Al-Ghazâlî was one of the biggest critics of Aristotelian sciences of all times.
12/28
Aristotle's analogy was a metaphysical stalemate. Sure, a man would pick between food and water even if as hungry as thirsty, but how? To resolve this, Al-Ghazâlî introduced free will in an Arabic volume titled Tahāfut al-Falāsifaʰ (The Incoherence of the Philosophers).
Aristotle's analogy was a metaphysical stalemate. Sure, a man would pick between food and water even if as hungry as thirsty, but how? To resolve this, Al-Ghazâlî introduced free will in an Arabic volume titled Tahāfut al-Falāsifaʰ (The Incoherence of the Philosophers).
13/28
What Al-Ghazâlî propounded is referred to as, in philosophical terms, hard determinism. It's the idea that free will exists, but within the confines of forces outside of one's control. To illustrate his idea, Al-Ghazâlî replaced food and water with dates.
What Al-Ghazâlî propounded is referred to as, in philosophical terms, hard determinism. It's the idea that free will exists, but within the confines of forces outside of one's control. To illustrate his idea, Al-Ghazâlî replaced food and water with dates.
14/28
Here's Al-Ghazâlî's thought experiment:
"Suppose two similar dates in front of a man, who has a strong desire for them but who is unable to take them both. Surely he will take one of them."
He attributed this random choice to free will.
Here's Al-Ghazâlî's thought experiment:
"Suppose two similar dates in front of a man, who has a strong desire for them but who is unable to take them both. Surely he will take one of them."
He attributed this random choice to free will.
15/28
Al-Ghazâlî proposed as an aspect of human nature, the ability to choose between two identical choices. This innate faculty, he suggested, is the invisible deterministic force that informs man's free will. Of course, we aren't necessarily conscious of this influence.
Al-Ghazâlî proposed as an aspect of human nature, the ability to choose between two identical choices. This innate faculty, he suggested, is the invisible deterministic force that informs man's free will. Of course, we aren't necessarily conscious of this influence.
16/28
A counter to Al-Ghazâlî's idea would come almost a century later from Moorish Andalusia. Abū l-Walīd Muḥammad Ibn ʾAḥmad Ibn Rušd, Latinized as Averroes, was an Islamic jurist, philosopher, theologian, and most importantly, a fan of Aristotle's.
A counter to Al-Ghazâlî's idea would come almost a century later from Moorish Andalusia. Abū l-Walīd Muḥammad Ibn ʾAḥmad Ibn Rušd, Latinized as Averroes, was an Islamic jurist, philosopher, theologian, and most importantly, a fan of Aristotle's.
17/28
Averroes dedicated an entire volume titled Incoherence of the Incoherence to the defense of Arabic Aristotelians from Al-Ghazâlî's criticism. The volume itself was a critique of Al-Ghazâlî's Incoherence of the Philosophers.
Averroes dedicated an entire volume titled Incoherence of the Incoherence to the defense of Arabic Aristotelians from Al-Ghazâlî's criticism. The volume itself was a critique of Al-Ghazâlî's Incoherence of the Philosophers.
18/28
Averroes counters Al-Ghazâlî's question with a change in choices. The choice, according to him, isn't really between two identical dates, but between picking one date and not picking any. Now the choices are no longer identical, hence rationale over hard determinism.
Averroes counters Al-Ghazâlî's question with a change in choices. The choice, according to him, isn't really between two identical dates, but between picking one date and not picking any. Now the choices are no longer identical, hence rationale over hard determinism.
19/28
Aristotle, Al-Ghazâlî, and Averroes, were all revisited some time in the middle of the 14th century, about 150 years after Averroes died. This time it was a University of Paris arts teacher named Jean Buridan. Besides techer, Buridan was also an Aristotelian scholar.
Aristotle, Al-Ghazâlî, and Averroes, were all revisited some time in the middle of the 14th century, about 150 years after Averroes died. This time it was a University of Paris arts teacher named Jean Buridan. Besides techer, Buridan was also an Aristotelian scholar.
20/28
Buridan proposed:
"Should two courses be judged equal, then the will cannot break the deadlock, all it can do is to suspend judgement until the circumstances change, and the right course of action is clear."
He called it moral determinism.
Buridan proposed:
"Should two courses be judged equal, then the will cannot break the deadlock, all it can do is to suspend judgement until the circumstances change, and the right course of action is clear."
He called it moral determinism.
21/28
Per Buridan, reason alone could determine one's choices. There was no room for randomness. If you don't know what to pick, you wait until you know better.
Later satirists, in an attempt to make Buridan's analogy more accessible, introduced a donkey.
Per Buridan, reason alone could determine one's choices. There was no room for randomness. If you don't know what to pick, you wait until you know better.
Later satirists, in an attempt to make Buridan's analogy more accessible, introduced a donkey.
22/28
They took Al-Ghazâlî's example, replaced the man with a donkey, and dates with two identical bales of hay. And elucidated Buridan's idea as the donkey starving to death since he couldn't pick between the bales. It was a satire on Buridan's moral determinism.
They took Al-Ghazâlî's example, replaced the man with a donkey, and dates with two identical bales of hay. And elucidated Buridan's idea as the donkey starving to death since he couldn't pick between the bales. It was a satire on Buridan's moral determinism.
23/28
Although the donkey never featured in Buridan's own analogies, the association stuck. We call it Buridan's Ass (no, not his derrière).
It took 300 years for someone influential to finally call out the impracticality of Buridan's principle in most direct terms.
Although the donkey never featured in Buridan's own analogies, the association stuck. We call it Buridan's Ass (no, not his derrière).
It took 300 years for someone influential to finally call out the impracticality of Buridan's principle in most direct terms.
24/28
This critic was a Jewish thinker from Amsterdam by the name Baruch Espinoza, also known as Benedictus de Spinoza. Deeply inspired by René Descartes, Spinoza was one of the most towering figures of the Dutch Golden Age.
This critic was a Jewish thinker from Amsterdam by the name Baruch Espinoza, also known as Benedictus de Spinoza. Deeply inspired by René Descartes, Spinoza was one of the most towering figures of the Dutch Golden Age.
25/28
Spinoza started writing his magnum opus, "Ethica, ordine geometrico demonstrata" toward the end of his life and was already dead by the time it made the press. In this, Spinoza flat-out dismissed Buridan's ass as an irrational being.
Spinoza started writing his magnum opus, "Ethica, ordine geometrico demonstrata" toward the end of his life and was already dead by the time it made the press. In this, Spinoza flat-out dismissed Buridan's ass as an irrational being.
26/28
Almost all major thinkers since have more or less followed Spinoza's line of reasoning which itself jives well with what Averroes postulated back in the 12th century, that there's always, in layman terms, a tie-breaker. That one can never have two identical choices.
Almost all major thinkers since have more or less followed Spinoza's line of reasoning which itself jives well with what Averroes postulated back in the 12th century, that there's always, in layman terms, a tie-breaker. That one can never have two identical choices.
27/28
That's precisely what Aristotle said, if you recall. That a man even if equally hungry and thirsty, would still pick between food and water should circumstances present him with such a conundrum. He just didn't explain how, but he concluded all the same.
That's precisely what Aristotle said, if you recall. That a man even if equally hungry and thirsty, would still pick between food and water should circumstances present him with such a conundrum. He just didn't explain how, but he concluded all the same.
28/28
So that's the 2,300-year-old answer to all your dilemmas. Next time your heart says they're all equally bad, next time you're tempted by NOTA, recall this story.
Don't be Buridan's Ass, don't starve to death.
There's always a worst and always a best.
So that's the 2,300-year-old answer to all your dilemmas. Next time your heart says they're all equally bad, next time you're tempted by NOTA, recall this story.
Don't be Buridan's Ass, don't starve to death.
There's always a worst and always a best.
