# Bug in proof environment? [duplicate]

I am trying to give students an empty space for a proof. So it should start the with the word Proof then empty space, then the little square at the bottom of the empty space. When I specify the empty space (1cm in the example below), the Proof and qed symbol is put on the same line and I get the empty space before or after this line. Why does proof do this?

\documentclass{article}

\usepackage{amsthm}

\begin{document}
Regular proof environment with space
\begin{proof}
\vspace{1cm}
\end{proof}
The same but starting with tilde
\begin{proof}
~\vspace{1cm}
\end{proof}
Some text after the proof
\end{document}


• \vspace, when entered in horizontal mode, is deferred until the end of the paragraph. One way to get around this is to put something invisible in the proof: \begin{proof} \par and then the \vspace. (I'm putting this in a comment since I am unable to test, and I don't like to post untested answers.) – barbara beeton Mar 27 '19 at 2:10
• The suggestion of @barbarabeeton works, thanks. – Máté Wierdl Mar 27 '19 at 12:36

As @barbara mentioned, I also think the proof environment is actually a list and you need to set the list entry (have a look in How to add blank space in proof environment)

So you can use a "placeholder" or a empty box and after that paragraph call the vspace:

\documentclass{article}
\usepackage{amsthm}

\begin{document}

Prove that...
\begin{proof}
\mbox{}\par
\vspace{3cm}
\end{proof}

\end{document}


• This works, though Barbara's answer is a bit less typing. – Máté Wierdl Mar 27 '19 at 12:34