It depends if you want to be knowledgeable "about" philosophy and knowledge or if you want to apply it to you life. * K.Popper (in both cases;): _Open society

It depends if you want to be knowledgeable "about" philosophy and knowledge or if you want to apply it to you life. * K.Popper (in both cases;): _Open society and its ennemies_ http://www.archive.org/stream/opensocietyandit033120mbp#page/n7/mode/2up http://www.archive.org/stream/opensocietyandit033120mbp#page... for "Ars Vitae" (applicable to one's life) * Plato: _Gorgias_ * Marc Aurélius: _Meditations_ * Friedrich Nietzsche: _Beyond good & evil_ I agree with others on Hume, Russell, Husserl. Another great thinker while he does not pretend to be a philosopher is Dan Sperber, I think of 2 books * Dan Sperber (with Deirdre Wilson) _Relevance. Communication and Cognition_ (Blackwell, 1986) * Sperber, Dan (1996) Explaining culture: _A naturalistic approach._ (Oxford: Blackwell) Finally philosophical literature: * Doistoievski: _The Brothers Karamazov_ (question of God is asked)