A riddle named "philosophy" A philosopher is a blind man looking in a dark room for a black cat that is not there (William James) Philosophy is the most enigmatic of human intellectual endeavors. Does it have a definite subject? And if not how can anything meaningful be said in it? How is it possible that 2500 years of research have not led to any progress toward solution of its main problems? Ron Aharoni, a mathematics professor at the Technion, proposes a theory on the nature of philosophy, that answers these riddles. According to this theory, philosophizing starts from a faulty premise on the structure of the concepts used for the investigation. Once this error is rectified, the major philosophical problems skepticism, Determinism-Free Will and the Mind-Body problem disappear, while the other problems lose their philosophical flavor.