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Theorems · Theorem · category theory

CategoryTheory.Limits.eq_of_epi_equalizer

∀ {C : Type u} {X Y : C} [inst : CategoryTheory.Category.{v, u} C] {f g : X ⟶ Y}
  [inst_1 : CategoryTheory.Limits.HasEqualizer f g] [CategoryTheory.Epi (CategoryTheory.Limits.equalizer.ι f g)], f = g

If the equalizer of two morphisms is an epimorphism, then the two morphisms are equal.

Defined in
Mathlib.CategoryTheory.Limits.Shapes.Equalizers
Cited by
6 results in Mathlib
Foundations
Depth 28 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
CategoryTheory.CategoryCategoryTheory.Limits.HasEqualizerCategoryTheory.Epi

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