Kerodon

$\Newextarrow{\xRightarrow}{5,5}{0x21D2}$
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$

Example 3.1.1.2. Let $X_{}$ be a simplicial set. Then the projection map $X_{} \rightarrow \Delta ^0$ is a Kan fibration if and only if $X_{}$ is a Kan complex.