CatDat

Implication Details

Assumptions: cokernelskernelspreadditive

Conclusions: quotients of congruences

Reason: For any congruence EE on an object XX of a preadditive category, let E0E_0 be the kernel of p2:EXp_2 : E \to X. The restriction of p1p_1 to E0E_0 is a monomorphism. We can then see that EE must be the pullback of p1p2:EXp_1 - p_2 : E \to X and E0XE_0 \hookrightarrow X. Then the cokernel of E0XE_0 \hookrightarrow X is a quotient of EE.