/sci/ - Science & Math

Hi /sci/,

I have 3 questions:
1. I was wondering what the normal "leveling up" is in math. What does one usually learn after calculus and after that and after that? Or isn't there a standard route and/or when does it start to differentiate?
2. I've taken math until pre-calc, but I've also taken classes in propositional, predicate and modal logic and I did some set theory. How hard is calculus and what comes after that compared to that shizzle?
3. What would be the minimum IQ-score for a Fields Medal? I'm not implying that I'm able to get one or planning to get one...although I know it's every /sci/entist secret wet dream.

I've been reading /sci/ for a few days now and I've seen a few threads about how logic/math is most fundamental. I don't know much about logic and my math hasn't been very rigorous or formal, so should I start by getting an intro logic textbook? Is there one you'd recommend?

Or what do you consider the optimum path to becoming /sci/?