# Remove numbering from fitch.sty natural deduction

Johan Klüwer has a great package fitch.sty for typsetting natural deduction proofs. However I want to define some deduction rules in the vertical fitch format and it does not make sense to have the numbering on the left side since there could be arbitrarily many lines in between the lines with the relevant information. For example, I want to drop the line numbering so that I can indicate that there need not bee exactly one line between the line with A and the line with B:

\documentclass{article}
\usepackage{fitch}

\begin{document}

\begin{equation*}
\begin{fitch}
\fh A & Hypothesis \\
\fa \vdots \\
\fa B & derrived from hypothesis\\
A \to B
\end{fitch}
\end{equation*}

\end{document}

• Unfortunately, that code is not licensed. So it is impossible to tell what may be done with it, including whether it is permissible to modify, distribute or, even, use it. – cfr Jan 29 '18 at 2:39
• Hypothetically, however, I would suggest \renewcommand\formatfitchcounter[1]{\relax} in a local group with the rules you want typeset this way. – cfr Jan 29 '18 at 2:41