I’m going to go with a few assumptions here: a) You don’t do this full time. b) By “bottoms up” you just mean “with firm grasp on fundamentals”, not logic/set/category/type theory approach. c) You are skilled with programming/software in general. In a way, you’re ahead of math peers in that you don’t need to do a lot of problems by hand, and can develop intuition much faster through many software tools available. Eve…
The Princeton Companion to Mathematics is a good resource consisting of a huge collection of detailed articles on many mathematical subjects by knowledgeable contributors. It requires no specialized background and is curated by Fields Medalist Tim Gowers. Whoever reads it from cover to cover is my hero, but failing that there's always an interesting article to jump to. Don't just be a consumer but write something as…
Fantastic quotes and points, thanks for sharing.