Lemma 115.26.6. Let $R$ be a ring. Let $E$ be an $R$-module. The following are equivalent

$E$ is an injective $R$-module, and

given an ideal $I \subset R$ and a module map $\varphi : I \to E$ there exists an extension of $\varphi $ to an $R$-module map $R \to E$.

## Comments (2)

Comment #2764 by Dario Weißmann on

Comment #2877 by Johan on