Why is it suggested to "范畴论" translated with "general nonsense"? "范畴论" seems to be the correct term for "Category Theory", a relatively modern and popular branch of mathematics. Therefore I find the suggested translation "general nonsense", I checked various dictionaries and platforms, a bit troublesome or maybe undiplomatic. 

Is there a reason for this  suggestion of translation?
https://en.m.wikipedia.org/wiki/Abstract_nonsense


  In mathematics, abstract nonsense, general abstract nonsense, and general nonsense are terms used by mathematicians to describe abstract methods related to category theory and homological algebra. More generally, “abstract nonsense” may refer to a proof that relies on category-theoretic methods, or even to the study of category theory itself.