Remark 8.5.1.31. Corollary 8.5.1.30 asserts that the map $\sigma : \Delta ^2 \rightarrow \operatorname{N}_{\bullet }( \operatorname{Ret})$ exhibits $\operatorname{N}_{\bullet }( \operatorname{Ret})$ as a localization of the standard $2$-simplex $\Delta ^2$ with respect to the “long edge” $0 \rightarrow 2$ (see Definition 6.3.1.9).
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$