Variant 1.4.2.8. If $X$ is a Kan complex, then the opposite simplicial set $X^{\operatorname{op}}$ is also a Kan complex.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$
Variant 1.4.2.8. If $X$ is a Kan complex, then the opposite simplicial set $X^{\operatorname{op}}$ is also a Kan complex.