Nam Nguyen wrote: > > On 14/03/2013 1:14 PM, Shmuel (Seymour J.) Metz wrote:
> > > > ZFC+(V=L) is not ZFC. > > Right. But there's also a sense that an Abelian group is a group.
I don't know why you write "there's also a sense", an Abelian group is a group without doubt or qualification. But the theory of Abelian groups is not the theory of groups. That is more analogous to Shmuel Metz's ZFC+(V=L) is not ZFC. ZFC+(V=L) and ZFC are theories, not structures or classes of structures.
-- When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him. Jonathan Swift: Thoughts on Various Subjects, Moral and Diverting