Single Idea 15441

[catalogued under 9. Objects / C. Structure of Objects / 1. Structure of an Object]

Full Idea

What is wrong with the pictorial conception is that if the structural universal 'methane' is to be an isomorph of the molecules that are its instances, it must have the universal 'hydrogen' as a part not just once, but four times over.


Methane is CH4

Gist of Idea

The structural universal 'methane' needs the universal 'hydrogen' four times over


David Lewis (Against Structural Universals [1986], 'The pictorial')

Book Reference

Lewis,David: 'Papers in Metaphysics and Epistemology' [CUP 1999], p.91

A Reaction

The point is that if hydrogen is a universal it must be unique, so there can't be four of them. To me this smacks of the hopeless mess theologians get into, because of bad premisses. Drop universals, and avoid this kind of stuff.

Related Idea

Idea 15439 The 'pictorial' view of structural universals says they are wholes made of universals as parts [Lewis]