Nonzero: The Logic of Human Destiny by Robert Wright about biological and cultural evolution shaped and directed by "non-zero-sumness" or synergetic interactions.
Godel, Escher, Bach: An Eternal Golden Braid by Douglas Hofstadter. Brilliant synthesis of thoughts on logic, reasoning, programming, artificial intelligence,…
Zen and the Art of Motorcycle Maintenance by Robert Pirsig. The only book I've read twice (at about 18 and again in late twenties.) Deep thoughts on the contrast between "pragmatic" vs "romantic" perspectives on life, and the meaning of "Quality".