Full Idea
'Cats are animals' has turned out to be a necessary truth.
Gist of Idea
'Cats are animals' has turned out to be a necessary truth
Source
Saul A. Kripke (Naming and Necessity lectures [1970], Lecture 3)
Book Reference
Kripke,Saul: 'Naming and Necessity' [Blackwell 1980], p.138
A Reaction
False! As Putnam has pointed out, we could yet discover that cats are subtly designed alien robots. This is a revealing error by Kripke, showing his desire to move from a useful logical clarification to an excessively amibitious metaphysics.