How can I indent the paragraphs which follow a heading?

Question

I am trying to write a text where the first line of each paragraph has an indent(tab). But for some reason, in a chapter or a section or subsection, except the first paragraph, the rest of the paragraphs have an indent(tab). Is there any way to add an indent to the first paragraph in a chapter or section or subsection?

Answer 1

The easiest method is to call

\usepackage{indentfirst}

in your preamble. This package is included in all LaTeX distributions.

Answer 2

You could redefine the internal macro \@afterheading for setting \@afterindent to true:

\documentclass{book}
\makeatletter
\let\orig@afterheading\@afterheading
\def\@afterheading{%
   \@afterindenttrue
  \orig@afterheading}
\makeatother
\begin{document}
\chapter{One}
text
\section{one}
text
\end{document}

This works without an additional package. Perhaps consider using the titlesec package which is very useful for customizing format and spacing of headings. Its command \titlespacing can make an indentation, but if used with a star such as \titlespacing* the indentation is removed.

Answer 3

The first paragraph after a section heading is not indented by default in most document classes (or rather its indentation is removed, which is why \indent doesn't help you either). If you do like all your paragraphs indented then the correct thing to do is to change this default. There is a package called indentfirst that precisely does this for you.

There are a couple of other packages that may influence/change the default behavior of the document class, e.g., titlesec has an option to specify how the behavior should be and the frenchb option for babel automatically adds indentation as this is a common typographically rule for French documents. And there may be others.

If for some (strange) reason you only want a single paragraph indented then try \indent\indent, the first will be swallowed but the second should survive.

Answer 4

Another simple solution is to include

\usepackage[indentafter]{titlesec}

in your document. This is a good choice if you also intend to use the package titlesec for other purposes.

Answer 5

Let's say you want to write an article. Here's a skeleton.

\documentclass{article}

% add here the packages you need, for instance
\usepackage[utf8]{inputenc}

\begin{document}

\author{Andrew}
\title{A paper about something}

\maketitle

\tableofcontents
\newpage % if you really want to go to a new page

\section{Introduction}

This is the first paragraph, that should be captivating the attention
of the readers. We say here some very important things, and then
we will proceed to explain what's in the paper.

This paragraph will be indented, since it's the second after a
section title. Note that paragraphs should be separated by a
blank line and not by a double backslash.

\section{Main results}

This paragraph is not indented. However, if your typographical
standard wants that also the first paragraph after a section
title is indented, it can be done.

The second paragraph \emph{is indented} anyway.

\subsection{Preliminaries}

Not the one following a subsection title.

\end{document}

The trick for indenting all paragraphs, including the first after a title, is to load

\usepackage{indentfirst}

Some people swear that sometimes it's good to go to a new line without indentation and this is attained by using \\ to terminate the paragraph. Those people are wrong.