Indent theorem body (excluding the title)

Question

I'd like to define custom environments in which the body is indented in contrast to the body/the first line of the environment. An example could look like this

In particular not every environment should be indented. How can I approach this problem? I'm using amsthm. Thank you for you help.

Please show a minimal working example (MWE) of how your currently define/use your environent. Please also be more specific about "in particular not every environment should be indented". — leandriis, Dec 15 '19 at 09:48
This question covers the same request: Indent Theorem like \hangindent, but for multiple paragraphs — barbara beeton, Dec 15 '19 at 15:26

score 0 · Answer 1 · answered Dec 15 '19 at 13:27

It is easy with etoolbox:

\documentclass[ngerman]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{babel}
\usepackage{amsthm, amssymb}%
\usepackage{etoolbox} 
\usepackage{lipsum}

\theoremstyle{plain}
\newtheorem{lemma}{Lemma}
\BeforeBeginEnvironment{lemma}{\par\hangindent=2.5em}
\AfterEndEnvironment{lemma}{\par}

\begin{document}
\setcounter{lemma}{2}

\lipsum[2]
\begin{lemma}
Sei $\mathcal{M}_{μ}$ die Familie der $\mu$-meßbaren Teilmengen von $X$. Dann ist $\mathcal{M}_{μ}$ eine $\sigma$-Algebra über $X$, und $\mu$ eingeschränkt auf $\mathcal{M}_{μ}$ ist ein (positives) Maß auf $\mathcal{M}_{μ}$.
\end{lemma}
\lipsum[3]

\end{document}

Indent theorem body (excluding the title)

1 Answers1