Not PP, but I can guess at a few, at least: - It easier to see the 'essence' of an equation/problem when all irrelevant detail is omitted. - Many concepts are

Not PP, but I can guess at a few, at least: - It easier to see the 'essence' of an equation/problem when all irrelevant detail is omitted. - Many concepts are so general that you'd need a small essay to have a 'descriptive' name, rather than just, say, x. - Algebraic manipulation often leads to non-intuitive concepts in intermediate calculations, e.g. meter-dollars. It's handy to be able to just call such a thing 'a' (or whatever) if it helps make calculations easier.