Show that a map is an epimorphism iff its pushout with itself is its target. This is the dual of the corresponding proof for monomorphisms, which is given in the post.

]]>I am working on a project, and I need to know the proof of the corollary stating that (Being an epimorphism is a “colimit property”: more precisely, any functor which preserves pushouts (in particular any functor which preserves finite colimits, in particular any functor which preserves all colimits) preserves epimorphisms.) so could you please tell me where I can find the proof for this corollary?

All best,

Adnan ]]>

I actually can’t either! I’ve posted a math.SE question about this.

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