I'm also reading Gödel, Escher, Bach The first few chapters were invaluable to me with discrete maths - it was far easier to think inside a fixed formal system

I'm also reading Gödel, Escher, Bach The first few chapters were invaluable to me with discrete maths - it was far easier to think inside a fixed formal system when I had experienced it within the book first. The remaining chapters are all fascinating as well. Only bad point is I find it very tiring to read, I can't manage more than a couple of chapters in one sitting.