Example 9.3.3.5. Let $\operatorname{\mathcal{C}}$ be an $\infty $-category. For $n \leq -2$, a morphism $f: X \rightarrow Y$ of $\operatorname{\mathcal{C}}$ is $n$-truncated if and only if it is an isomorphism. See Example 3.5.9.2.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$