Kerodon

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

Remark 8.5.3.4. The simplicial set $\operatorname{N}_{\bullet }( \operatorname{Idem})$ is weakly contractible. This is a special case of Lemma 3.4.5.9, applied to the (discrete) category $[0]$.