This is an old revision of the document!
Epimorphism
Collection
context | ${\bf C}$ … category |
definiendum | $f \in\mathrm{it} $ |
inclusion | $f:{\bf C}[A,B]$ |
postulate | $\langle B,\prod_{B}1_A\rangle$ … pushout of $f$ along itself |
Discussion
See Monomorphism.
In ${\bf{Set}}$ the epimorphisms are the surjections. But people like to point out that in general, epis are quite different from surjections and also more difficult to classify (as opposed to monos, which mostly behave exactly like injections).
Reference
Requirements
todo