Full Idea
It is an established experimental fact ...that every single fundamental particle in the universe is the same and identical to all other particles of the same type.
Gist of Idea
Experiments show that fundamental particles of one type are identical
Source
Graham Farmelo (The Strangest Man [2009], 07)
Book Reference
Farmelo,Graham: 'The Strangest Man [Paul Dirac]' [Faber 2009], p.102
A Reaction
A loud groan is heard from the tomb of Leibniz. I'm unclear how experiments can establish this. If electrons have internal structure (which is not ruled out) then uniformity is highly unlikely.
Related Ideas
Idea 12971 If two individuals could be indistinguishable, there could be no principle of individuation [Leibniz]
Idea 13075 No two things are quite the same, so there must be an internal principle of distinction [Leibniz]
Idea 21205 Many physicists believe particles have further structure, if only we could see it [Martin,BR]