[Tex/LaTex] No indent in the first paragraph in amsart

Question

I would like to remove all the first indentations in amsart, so I am seeking for an "indentfirst=false" command. Note that amsart do indents the first paragraphs by default (so the suggested solutions of 'No indent in the first paragraph in a section?', i.e. 'do nothing' are not relevant here).

Answer 1

You seem to agree with Tschichold about indentation.

Tschichold's opinion is that the only case where a new paragraph should not have an indentation is when it follows a centered title. The AMS thinks differently and decided for no indentation only in titles set flush left and run in (all the levels under \section).

If your paper in intended for submission to the AMS, don't change the setup; the editorial staff will add whatever they need (a new class, probably) and typeset the paper according to their wishes.

You're free to use amsart for your own writings and there's no copyright issue if you modify the appearance: there is nothing in the licensing information that prohibits using the class; the only requirement is that one can't modify the class file and redistribute the changed version with the same name.

How can you do? Just patch the relevant command.

\documentclass{amsart}
\usepackage{etoolbox}

\makeatletter
\patchcmd{\@startsection}
  {\@afterindenttrue}
  {\@afterindentfalse}
  {}{}
\makeatother

\begin{document}
\section{A}
Some text to show if there is an indentation
and other text follows and other text follows
and other text follows and other text follows
and other text follows and other text follows.

\subsection{B}

Some text to show if there is an indentation
and other text follows and other text follows
and other text follows and other text follows
and other text follows and other text follows.
\end{document}