I am looking for generally accepted standards or "best practices" on how to space logical expressions. I am particularly interested in expressions of the form:
My question arose after I read the following principle somewhere in this site: there should be more space around more important elements. In the equation a + b = c, the relation = is more important than the binary operation +, and therefore, it makes sense to have more space around it. That is why \mathrel{} adds more space than mathbin{}.
However, in the logical expression (a=b \land b=c) \implies a=c, I am not sure that = is the most important element. Here, my intuition tells me that \land should have more space than =, and maybe \land and \implies should have a similar amount of space. Without it, there might be ambiguity between ((a=b)\land(b=c)) and (a = (b\land b) = c). However, the default space is \mathrel{} for =, \mathbin{} for \land, and something that looks bigger for \implies.
I would like to know the answer to the following specific questions
- Are there any style manuals that address the best practices on how to space logical expressions?
- What are some generally accepted principles on how to set space around binary relations, conjunctions, and implications in displayed logical formulas?
- If using
\text{and}inside a displayed logical formula, what is the right amount of space to use around it? - Why does LaTeX assign different space to
\impliesand\iffbut not\landand\lor?
I understand that some of these questions could be opinion-based. I hope this question does not go against any community policies.
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[
(a=b \land b=c) \implies a=c
\]
\[
(a=b\ \text{and}\ b=c) \implies a=c
\]
\end{document}
