Jenny asked:

What is the main philosophical teaching of the philosopher Aristotle? (in 1 or 2 sentences).

Answer by Craig Skinner

Other than as a bit of fun, I dont think there is point to so compressing this very great philosopher’s vast output.

But, in that spirit, how about:

‘Aristotle teaches a system of logic, since expanded but not retracted, a four-cause account of explanation, four categories of being, a this-world-only rejection of Platonic forms, immanent universals, and the good life as pursuit, in a community, of the proper ends for humans.’

Or how about a bad limerick I have just made up:

    His logic’s grown symbols since yore
    Categories and causes still four
    The good life depends
    On virtue and ends
    And one world’s enough, forms mere lore.

But why stop at two sentences. How about one, a phrase, or a word:

Heraclitus: flux
Democritus: atoms and the void
Plato: forms are reality
Descartes: doubt
Locke: blank slate
Berkeley: no matter
Hume: slavish reason, scepticism
Leibniz: monadism
Kant: categories and duty
Mill: utilitarianism
Russell: descriptions
Lewis: possible worlds are real
Quine: dogmas disputed
Gettier: justified true belief isn’t knowledge
Goodman: gruesome

For McTaggart, we have no time, whilst keeping an open question about Moore.

However, learning anything worthwhile in philosophy is hard work with no shortcuts, but this can still be fun.