Single Idea 15734

[catalogued under 8. Modes of Existence / B. Properties / 11. Properties as Sets]

Full Idea

A property that is instantiated in a relative way (such as being a father or a son) could not be the set of its instances? Is the thing to be included in the set or not?

Gist of Idea

If a property is relative, such as being a father or son, then set membership seems relative too


David Lewis (On the Plurality of Worlds [1986], 1.5)

Book Reference

Lewis,David: 'On the Plurality of Worlds' [Blackwell 2001], p.52

A Reaction

He says philosophers contrive ways to define properties as functions, but he prefers to call such properties 'relations', and define them that way. It never even occurred to me that 'being a son' was one of my properties, but what do I know?