Full Idea
Why is man not Animal and Biped together? Then it will not be by participating in Man (or any other unity) that men exist but by doing so in two things, Animal and Biped. Then man would not be a unity but a plurality.
Gist of Idea
If men exist by participating in two forms (Animal and Biped), they are plural, not unities
Source
Aristotle (Metaphysics [c.324 BCE], 1045a17)
Book Reference
Aristotle: 'Metaphysics', ed/tr. Lawson-Tancred,Hugh [Penguin 1998], p.249
A Reaction
This is perhaps Aristotle's deepest metaphysical objection to the whole Plato programme, that it blocks a decent account of the unity of particulars, on which our whole understanding of the world rests.
Related Idea
Idea 16109 Things are a unity because there is no clash between potential matter and actual shape/form [Aristotle]