>>849 >>850 Thank you. I don't mind if it doesn't cover everything in depth. But you say that Amman and Escher is a good introduction to proof-based math and compare it to Zorich. I can't comment on that but I would be lying if I didn't say that I didn't have difficulties with Zorich. Are they comparable in diffculty? I have covered Courant's calculus vol. 1 beforehand and I regret it slightly.