#######################
\begin{proof}
bla bla bla
\begin{wrapfigure}{L}{0.5 \textwidth}
\includegraphics[width = 0.2 \textwidth]{name}
\end{wrapfigure}
bla bla bla bla
\end{proof}
########################
The proof environment is implemented as a trivlist
environment. Any list environment sets the paragraph
parameters (things like how much indentation on how
many lines, etc.) However wrapfigure needs to take
control of these and so there is a conflict.
It is not hard to mimic the proof environment:
\noindent\textit{Proof.} bla bla bla
\begin{wrapfigure}{L}{0.5 \textwidth}
\includegraphics[width = 0.2 \textwidth]{name}
\end{wrapfigure}
bla bla bla bla.\qed
As I am not sure what exactly you want this to do, I cannot
say if this will do it. I do believe, howver, that a
wrapfigure environment takes effect on the _next_ available
paragraph, not the current one.
Also, I ran this with the amsart class, the wrapfig
environment and a \rule{0.2\textwidth}{0.1\textwidth}
replacing the \includegraphics. I would not have to
guess if you had included a minimal document wrapper
for your code, and used an appropriately sized \rule
yourself.
Dan
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