# Customize the display of a theorem

I have a theorem for which I do not have a proof. What I mean is that I have a paragraph under it, but I do not want it to start with the word Proof. Instead I want that only the first line of the paragraph to be indented.

This is what I have so far:

\documentclass[a4paper,12pt,twoside]{report}
\usepackage{mystyle}
\setlength{\parskip}{0.3cm}
\setlength{\parindent}{0pt}

\newtheorem{theorem}[lemma]{Theorem}

\begin{document}

\begin{theorem}
This is a theorem.
\end{theorem}
"Here begins the explanation
which is continued here
and here."

\end{document}


I have seen that I could use \indent in front of it, but this does not apply in my case since I have \setlength{\parindent}{0pt} before the start of the document.

How can I indent only the first line?

• \hspace*{1cm}. By the way, why did you kill the parindent? Jun 25, 2014 at 23:05
• \hspace*{15pt} Your paragraph. However mixing indented and non-indented paragraphs is rather not a good typographic convention. Jun 25, 2014 at 23:06
• \parindent is usually 20pt in the basic document classes.
– Werner
Jun 25, 2014 at 23:07
• Either you indent all your paragraphs (theorems are an exception because they are labelled) or none. Indent them and don't set a nonzero \parskip, your readers will be grateful. Jun 25, 2014 at 23:10
• @Jessy09 I read lots of books and papers in English and I couldn't find significant examples of non indented paragraphs. Jun 25, 2014 at 23:12