Ceci est une ancienne révision du document !
— section: The joy of TeX errors date: 2014-06-10 —
# `\normalsize` not defined
The LaTeX error: ```latex The font size command \normalsize is not defined: there is probably something wrong with the class file. ``` reports something pretty fundamental (document base font size has not been set, something the document class does for you). It _can_, in principle, be a problem with the document class, but is more often caused by the user forgetting to start their document with a `\documentclass` command.