# Kerodon

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

Go back to the page of Theorem 3.4.4.4.

Comment #1502 by Ken on

In the second step of the proof, why can we replace $A$ with $A\times _C \overline{C}$? There doesn't seem to exist an obvious map $A\times _C \overline{C}\to \overline{B}$.

Comment #1509 by Kerodon on

Oops! Yes, that argument needs to be modified. Thanks!

There are also:

• 5 comment(s) on Chapter 3: Kan Complexes
• 4 comment(s) on Section 3.4: Homotopy Pullback and Homotopy Pushout Squares
• 2 comment(s) on Subsection 3.4.4: Mather's First Cube Theorem

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