Projective Geometry: a boundless domain of countless fields where reals and imaginaries, finites and infinites, enter on equal terms, where the spirit delights in the artistic balance and symmetric interplay of a kind of conceptual and logical counterpoint - an enchanted realm where thought is double and flows throughout in parallel streams.

The Human Worth of Rigorous Thinking: Essays and Addresses, Chapter XI (p. 278), Columbia University Press. 1916