61 - Nobody’s Perfect: the Stoics on Knowledge

The Stoics think there could be a perfect sage, so wise that he is never wrong. Is this a big mistake? Peter investigates their epistemology to find out.

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Further Reading: 

• J.E. Annas, “Stoic Epistemology,” and G. Striker, “The Problem of the Criterion,” in S. Everson, Epistemology (Cambridge: 1990).

• S. Bobzien, “Chrysippus and the Epistemic Theory of Vagueness,” Proceedings of the Aristotelian Society 102 (2002), 217-238.

• M. Frede, “The Stoic Notion of a Lekton,” in S. Everson, Language (Cambridge: 1994), 109-28.

• M. Frede, “Stoics and Skeptics on Clear and Distinct Impressions,” in Frede, Essays in Ancient Philosophy (Oxford: 1987), 151-78.

• M. Mignucci, “The Liar Paradox and the Stoics,” in K. Ierodiakonou (ed.), Topics in Stoic Philosophy (Oxford: 1999), 54-70.

• F.H. Sandbach, “Phantasia Kataleptike,” in A.A. Long, Problems in Stoicism (London: 1971).

Ted's picture

The Sorites Paradox and a 5 year old


I was listening to your podcast on the Stoics and Epistimology on the way home from work one day, and when I got home, I told my 9 year old daughter and 5 year old son the Sorities paradox. As I went through it, my daughter said that adding the 18th grain would make a heap, so I asked, of course, how can adding just one grain make a heap, and my son Ollie said, "no dad, you're not adding the one grain to the pile, you're adding the whole pile to the one grain; that's why it's now a heap". I may be as impartial as I am classically educated, but that's the best solution I've heard. If nothing else, it shows an amazing grasp of the commutative property of addition, and is a lot more ballsy than Chrysippus's solution!

You may not feel the same, but I can't wait for your summer break to end!

Thanks again for your podcasts.

Peter Adamson's picture

Out of the mouths of babes

Thanks, that's a great story! Maybe you have a future philosopher in the making there. I agree, it's admirable that unlike certain Stoics we could name, Ollie was at least ready to take a stand.

The next episode goes up Sunday!


peter l's picture

every hair is numbered ...

I think the answer to this 'adding a grain of sand to create a heap problem' is simply to say ...

"you asked me to decide when I would call this a heap if you added sand grain by grain so I did. in this situation x grains isn't a heap but x+1 is ... i'm not saying I would apply the same principle in a different situation.
for instance, i'm not going to ask someone ... 'who left that heap of sand on my desk? well at least there's a lot of grains there. i'm not sure because obviously I haven't counted the grains ...' "

Peter Adamson's picture


That's a nice idea: it sounds a bit like just biting the bullet and accepting one of the supposedly absurd claims, namely that n grains is not a heap but n+1 is. But you might be right that the context in which one would admit this could be crucial. Actually I recently heard an episode of the Elucidations podcast that argued for a version of this solution, arguing that one could perhaps solve the paradox by invoking context as you are doing. Worth a listen. Here is the link.