@sinbad I've done math at UNI, I dropped at the 2nd year but I've done some exams ( Linear Algebra, Algebra, Numerical Calculus ) it is true "if you can't think more abstract you CAN NOT grasp 'higher math'. Math *CAN* be *ALMOST ALL* applied into something, but that's really "applied math" NOT "pure math". Math is all about "generalizing concepts at max" so when you talk about "sum" it's the "act of summing" it's NOT limited to numbers, sets, vectors and what it means is "valid for everything".