As someone who is math-stupid, I totally find that my main difficulty in learning a new thing is that the "obvious parts" are not mentioned, or only in such pas

As someone who is math-stupid, I totally find that my main difficulty in learning a new thing is that the "obvious parts" are not mentioned, or only in such passing as to make clear to anyone that they should already know this.. I learn from the top down, I can't reverse that, but I can't "get all the fundamentals right first" and then work out from there... I need to scratch a lot of surface on the subject, then the fundamentals start to crystallize for me, so refreshing me on those obvious things in the context of what I'm learning, helps a lot.