more on this theme | more from this thinker
Full Idea
Armstrong says that if it can be proved a priori that a thing falls under a certain universal, then there is no such universal - and hence there is no universal of a thing being identical with itself.
Gist of Idea
A thing's self-identity can't be a universal, since we can know it a priori
Source
report of David M. Armstrong (A Theory of Universals [1978], II p.11) by Alex Oliver - The Metaphysics of Properties 11
Book Ref
-: 'Mind' [-], p.30
A Reaction
This is a distinctively Armstrongian view, based on his belief that universals must be instantiated, and must be discoverable a posteriori, as part of science. I'm baffled by self-identity, but I don't think this argument does the job.
| 15544 | If what is actual might have been impossible, we need S4 modal logic [Armstrong, by Lewis] |
| 7024 | Properties are universals, which are always instantiated [Armstrong, by Heil] |
| 9478 | Even if all properties are categorical, they may be denoted by dispositional predicates [Armstrong, by Bird] |
| 10729 | Universals explain resemblance and causal power [Armstrong, by Oliver] |
| 10728 | A thing's self-identity can't be a universal, since we can know it a priori [Armstrong, by Oliver] |
| 4031 | It doesn't follow that because there is a predicate there must therefore exist a property [Armstrong] |
| 10024 | The type-token distinction is the universal-particular distinction [Armstrong, by Hodes] |