Let Phi : P -----> S be the forgetful functor. Suppose that Phi (f) is an isomorphism. Is f then an isomorphism? Alternatively, suppose that Phi (G) and Phi (G') are isomorphic in S. Are G and G' then isomorphic in P?© BrainMass Inc. brainmass.com October 10, 2019, 3:38 am ad1c9bdddf
The solution assesses the forgetful functor.