Full Idea
The Way of Example says concrete entities are things like donkeys and puddles, but abstract entities are things like numbers. That gives us little guidance. There are no uncontroversial accounts of numbers, and donkeys and number differ in too many ways.
Gist of Idea
The Way of Example compares donkeys and numbers, but what is the difference, and what are numbers?
Source
David Lewis (On the Plurality of Worlds [1986], 1.7)
Book Reference
Lewis,David: 'On the Plurality of Worlds' [Blackwell 2001], p.82
A Reaction
That demolishes that fairly swiftly. It may be unfair to demand an agreed account of numbers, but the respect(s) in which donkeys and numbers differ needs to be spelled out before anything useful has been said.
Related Idea
Idea 15770 Some things cannot be defined, and only an analogy can be given [Aristotle]