It only assumes that single characters are desirable variable names. Especially if (as in Lisp) one does not draw a conceptual distinction between variables and

It only assumes that single characters are desirable variable names. Especially if (as in Lisp) one does not draw a conceptual distinction between variables and functions, it is common to see multi-letter variable names. Here is a typical example of a modern research paper: http://math.stanford.edu/~conrad/papers/locchar.pdf http://math.stanford.edu/~conrad/papers/locchar.pdf Most variables are one letter, but notice, e.g., GL in the fifth line (the General Linear group, not G times L), ker in the seventh, etc. One reason for brevity is that we like to write on paper and/or the chalkboard. And to answer your last question, I think math does concern itself with readability. Many mathematicians are obsessive about making sure that their work is as readable as possible, although unfortunately this is not universal.