Computer Science
Abelson & Sussman. Structure and Interpretation of Computer Programs.
Mathematics
Analysis
Spivak. Calculus.
Linear Algebra
Axler. Linear Algebra Done Right.
Probability
Jaynes. Probability Theory: The Logic of Science.
Proofs
Velleman. How to Prove It.
Set Theory
Halmos. Naive Set Theory.
Dauben. Georg Cantor: His Mathematics and Philosophy of the Infinite.
Logic & Foundations
Logic
Nagel & Newman. Goedel's Proof.
Philosophy of Mathematics
Courant & Robbins. What is Mathematics?
Russell. Introduction to Mathematical Philosophy.
Hilbert. Über das Unendliche.
Lakatos. A Renaissance of Empiricism in the Recent Philosophy of Mathematics?
Philosophy of Science
Poincaré. Science and Method.
Korzybski. Science and Sanity.
Kuhn. The Structure of Scientific Revolutions.
Humanities
Goethe. Faust.
Tufte. The Visual Display of Quantitative Information.
Philosophy
Wittgenstein. Philosophische Untersuchungen.
Kant. Kritik der reinen Vernunft.