Theophrastus (371 BC - 287 BC)

For Theophrastus, the necessity of universal principles derives from the corporeal and composite nature of the world. Space (defined as the arrangement and position of bodies) has no substance, and neither has time; time is an accident of motion, which in turn is the result of all activity. There is no difference between the way animals and human beings feel, sense, and reason. Man's happiness depends on not only personal effort but also external influences: "Life is ruled by fortune, not wisdom."