I'm slowly reading through Feynman's Lectures on Physics and I find myself wondering, is there an analogous book (or books) for math? By this, I mean a good approach to mathematics given through sweeping motions, appeals to intuition and an emphasis on modern perspectives over historical development.
What strikes me about Lectures on Physics is its conceptual orientation. It is easy to read in that I don't need a pen and paper at hand to work through details, but I also find it necessary to regularly stop and contemplate his ideas and examples. Content-wise, it is not at the level of a calculus book. My impression is that it covers much of what would constitute an undergraduate education in physics. Of course, finding a single book to cover an entire undergraduate mathematics curriculum is likely impossible! I'm looking for the same style, not necessarily the comprehensiveness.
This should really be a comment, but I don't have the reputation. I don't think any such book exists. In fact, I don't think that such a book is possible. There are two reasons for this.
Math, even at the undergraduate level, is much bigger than physics. It's not that it is impossible for anyone to understand everything that is taught to undergrads -- I certainly feel comfortable teaching any undergraduate-level course in my university. Rather, there are an enormous number of topics (calculus, geometry, linear algebra, abstract algebra, topology, partial differential equations, combinatorics, probability, etc) each of which has its own pattern of thought. At some point in your mathematical life, you will start to view them as one subject, but I don't think there is a way to teach undergraduates the foundational materials without having the topics fragment. A book that tried to describe all of them would be just too disjointed and incoherent.
You can learn a lot of physics without getting your hands dirty too much (via informal thought experiments, easy calculations, etc). This is basically the pattern in Feynmann's book -- it's all intuition and (almost) no detail. Math, however, doesn't work that way. You can't learn math without getting down to the details in a serious way. I guess you could tell a fun story, but the students would learn nothing from it.