the natural history
of abstract objects

My book will no doubt be flawed in many ways of which I am not yet aware, but there is one “sin” that I have intentionally committed, and for which I shall not repent: many of the arguments are not rigorous, at least as they stand. This is a serious crime if one believes that our mathematical theories are merely elaborate metal constructs, precariously hoisted aloft. Then rigor becomes the nerve-racking balancing act that prevents the entire structure from crashing down around us. But suppose one believes, as I do, that our mathematical theories are attempting to capture aspects of a robust Platonic world that is not of our making. I would the contend that an initial lack of rigor is a small price to pay if it allows the reader to see into this world more directly and pleasurably than would otherwise be possible.

—Tristan Needham, Visual Complex Analysis xi

combinatorics

algebraic synæsthesia

logarithms

trig

complex nummies

sequences and serieseses

calculus!!!

linalg