Example 3.3.7.2. Let $f: X \rightarrow S$ be a Kan fibration of simplicial sets, and let $s \in S$ be a vertex. If $S$ is weakly contractible, then Proposition 3.3.7.1 guarantees that the inclusion map $X_{s} \hookrightarrow X$ is a weak homotopy equivalence.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$