Home / D. Tradition, culture and religion / Part DIR
"Great thinkers ate meat."
someone's greatness in one field doesn't make all their practices right. Many great thinkers also defended hierarchies among humans that we now reject: Aristotle defended natural slavery. And the list cuts both ways: Pythagoras, Plutarch and Leonardo da Vinci are remembered as critics of eating meat. An authority only counts as an argument when it offers reasons, not by name alone.
Short answer
Great thinkers also got the customs of their time wrong: Aristotle argued that some humans were slaves by nature. So what they did doesn't prove it was right. Besides, the list cuts both ways: Pythagoras, Plutarch and Leonardo da Vinci are remembered for criticizing the eating of meat. What matters isn't who ate what, but what reasons each one gave.
For children
Very smart people make mistakes too. Some great thinkers of the past thought it was right for some people to be enslaved. They were very smart about many things, but they were wrong about that. Being smart doesn't mean everything a person does is right.
"Aristotle also defended slavery. Does that make slavery right?"
Como pode aparecer
"Aristotle ate meat."
"Einstein wasn't vegan."
"Do you think you're smarter than them?"
"Every genius in history ate meat."
"The philosophical tradition, for the most part, didn't condemn eating animals."
"Even philosophers don't agree." (which is E11)
The strongest version
"Aristotle ate meat. Einstein wasn't vegan. Do you think you're smarter than them?"
Strongest version (steelman):
- P1Many of history's greatest thinkers ate meat.
- P2These thinkers reflected deeply on ethics.
- P3If eating meat were clearly wrong, they would have noticed.
- CSo eating meat is probably not wrong.
P1 and P2 are true. The problem lies in P3: these same thinkers missed many injustices we now consider obvious.
The argument is valid. Its soundness fails at P3, which assumes great minds don't get the customs of their time wrong.
Full answer
- a
Reconstruction and diagnosis
The argument uses prestige in place of reasons:
Legitimate use of authority Fallacious use Citing the reasons a thinker gave Citing only the name or the habit Consulting experts in the field in question Treating general prestige as proof on any subject Considering the current consensus of experts Using practices from centuries ago as the standard - b
Where the argument breaks
1. It's an appeal to authority.
Someone's intellectual greatness doesn't make all their practices right. A brilliant physicist isn't an authority on ethics.
2. Great thinkers got a lot wrong.
Aristotle defended natural slavery and the inferiority of women (C9). Kant held that we have only indirect duties toward animals. Many thinkers accepted the hierarchies of their time.
3. The list cuts both ways.
Pythagoras and Plutarch criticized eating meat in antiquity, and Leonardo da Vinci is often remembered as a vegetarian. If the argument held, they would count too.
4. Habit isn't an argument.
What a thinker ate isn't part of their philosophy. More relevant would be the reasons they gave, and many never addressed the subject.
5. Today's ethics has arguments they didn't know.
Philosophy about animals has developed a great deal since the 1970s, and the science of animal sentience even more (E11).
- c
Data and sources
Source What it says Note Aristotle, *Politics*, book I Argues that some humans are slaves by nature Full text on Project Gutenberg; also used in C9 Plutarch, *On the Eating of Flesh* An ancient critique of eating meat Full text in English (Loeb), on LacusCurtius PhilPapers Survey 2020 About 26% of philosophers accept or lean toward vegetarianism as an ethical position, and about 18% toward veganism The question asks what is permissible to eat, not what each person eats; it shows that, among philosophers, the question is far from settled in favor of meat - d
The strongest counter-reply: the weight of the philosophical tradition
The most serious version doesn't cite habits but the tradition: most Western philosophy, from Aristotle to Kant, placed humans above animals, and that should count as evidence.
- e
Why the counter-reply doesn't reach the conclusion
The same tradition excluded many humans.
The classical philosophers' moral circle was narrow among humans too.
Tradition isn't an argument.
What matters are the reasons, and they're examined in the chapters of family A.
The tradition is changing.
A considerable share of today's philosophers accept or lean toward vegetarianism or veganism.
Reasoning errors
Logical
Is the form valid?
Appeal to authority
Convenient selection
Epistemological
Does the evidence support it?
Anachronism
Moral
Is the criterion coherent?
Outsourcing judgment
Biases
Authority bias
A prestigious person's opinion seems like proof
General literature on heuristics
Confirmation bias
Seeks only the authorities who confirm the habit
General literature on confirmation bias
Extrapolations
The principle being tested is: "if great thinkers did something, it isn't wrong".
If it applied to…SlaveryTap to see
It would be acceptable, because Aristotle defended it
No one accepts this
If it applied to…Excluding womenTap to see
It would be acceptable, because many philosophers defended it
No one accepts this
If it applied to…VegetarianismTap to see
It would also be right, because Pythagoras and Plutarch defended it
The argument cancels itself out
Contradictions
No one defends slavery because Aristotle did.
The selection reveals the real criterion.
Prestige decides nothing in those cases.
What the argument gets right
What is true
Great thinkers deserve to be heard, and it's reasonable to hesitate before concluding that all of them were wrong about something. The philosophical tradition has a lot to teach.
But
But listening to great thinkers means examining their reasons, not copying their habits. They themselves taught us to question customs, including the ones they followed.
Connections
Usually comes before
Usually comes after
Go deeper in Questão de Ética
Chapters from the open-access collection A Journey Through Animal Ethics that discuss this argument in more detail:
- Attempts to Justify Speciesism That Appeal to Authorities Vol. I, ch. 13
References
Philosophy
- Aristotle. *Politics*, book I.
- Plutarch. On the Eating of Flesh (De esu carnium).
- Philosophers on philosophy: the 2020 PhilPapers survey.