This is a collection of ambiguous, inconsistent, or just unpleasant conventions in mathematical notation, started by Christian Lawson-Perfect.
For each bit of notation, I want to collect examples, alternatives, and references to discussions about them.
The site's name is a reference to the question about why we start naming variables at 𝑥.
- Ambiguities - notations which can be reasonably interpreted in more than one way
- Conflicting definitions - definitions of terms or mathematical objects that don't have a single universally recognised meaning
- Handwriting - things that only or mainly come up in handwritten notation.
- Inconsistencies - conventions in notation that are inconsistent with each other, and conventions that could apply more generally, but for some reason don't.
- Language - problems to do with mathematical language.
- Local variations - conventions in notation that are particular to a place or group of people.
- Unpleasantness - conventions that just make you feel yuck.
How to contribute
You can edit this site, once you've created an account.
My aim is to describe conventions, without prescribing a correct notation.
While the tone of the site is informal, please avoid writing in a way that would make someone who follows a certain convention feel bad.