It's interesting, because I've always found (personally) that I didn't really understand any mathematics until it became a foundational tool for another form of

It's interesting, because I've always found (personally) that I didn't really understand any mathematics until it became a foundational tool for another form of math I needed to use. Although I took courses with proofs, they never really helped (I'm more engineer than mathematician). Notation is a huge help (and can be a hindrance) in grasping the So Addn<Multiply<Trig<Algebra<Calculus<ODE<PDE... unfortunately, I don't consider myself to have really learned PDEs although I can work with them. It's interesting to work with someone who CAN solve a novel PDE analytically, since their tool set is larger and they have real intuition.