diagram chasingとは 意味・読み方・使い方

名詞

diagram chasing (uncountable)

1. (mathematics, somewhat informal) Proof in stages, each of which, in general, depends on the previous stages and can be visualized by means of a diagram of morphisms.
   • 2016, Emily Riehl, Category Theory in Context (Aurora: Dover modern math originals)‎^[1], New York: Dover, ↑ISBN, OCLC 976394474, page x:

     Category theory also contributes new proof techniques, such as diagram chasing or arguments by duality; Steenrod called these methods “abstract nonsense.”³ The aim of this text is to introduce the language, philosophy, and basic theorems of category theory. A complementary objective is to put this theory into practice: studying functoriality in algebraic topology, naturality in group theory, and universal properties in algebra.

   To prove the five lemma, just use diagram chasing.