\chapter{Presenting Theories}\label{ch:thy-present}By now the reader should have become sufficiently acquainted with elementarytheory development in Isabelle/HOL\@. The following interlude describeshow to present theories in a typographicallypleasing manner. Isabelle provides a rich infrastructure for concrete syntaxof the underlying $\lambda$-calculus language (see{\S}\ref{sec:concrete-syntax}), as well as document preparation of theory textsbased on existing PDF-{\LaTeX} technology (see{\S}\ref{sec:document-preparation}).As pointed out by Leibniz\index{Leibniz, Gottfried Wilhelm} more than 300years ago, \emph{notions} are in principle more important than\emph{notations}, but suggestive textual representation of ideas is vital toreduce the mental effort to comprehend and apply them.\input{Documents/document/Documents.tex}%%% Local Variables: %%% mode: latex%%% TeX-master: t%%% End: