Full Idea
Parmenides: If a sail covering many people is one thing as a whole over many …would the sail as a whole be over each person, or would a part of it be over one person and another part over another?
Gist of Idea
Are many people covered by a whole sail, or each person by a part of it?
Source
Plato (Parmenides [c.366 BCE], 131c)
A Reaction
The standard idea of a universal is a concept which is one-over-many, but does a single horse embrace all the generalities included in the concept 'horse'? A puzzle for Plato's forms, but also for modern concepts.
Book Reference
Plato: 'Parmenides', ed/tr. Gill,M.L./Ryan,P. [Hackett 1996], p.132