A morphism in a pointed category is pseudo-epic when, for every , the equation forces . If a categorical cokernel exists, this is equivalent to that cokernel having a zero object as codomain. Indeed all zero composites then factor uniquely through zero; conversely the cokernel itself must be zero, and being both zero and epic forces its codomain to have identity zero, hence be a zero object. Every epimorphism is pseudo-epic. In a preadditive category, subtraction shows the converse: implies , hence . In a general pointed category no subtraction is available.
In a pointed category with categorical kernels and categorical cokernels, where every monomorphism is normal, every factors through as , with a pseudo-epimorphism. If , write . Then factors through , and the monic is a categorical kernel of some by normality. Since , the cokernel of forces . Hence factors through , forcing to be an isomorphism and therefore . This establishes the factorization without assuming the stronger abelian category axioms.
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