What Is Mathematics? An Elementary Approach to Ideas and Methods

Courant's method makes complex ideas accessible — I wonder how he decided which concepts to simplify and how that shaped the book.

Some sections delved into the nature of mathematical truth, which was fascinating but also made the reading feel more contemplative. Was that intentional?

Given all the new developments in math education, does Courant's approach still feel relevant or could it be updated for modern learners?