Philo of Alexandria was the first Middle Platonic thinker whose writings have largely survived. Otto Kaiser introduces the reader to his life, work and writings based on the extant manuscripts. Philo of Alexandria is one of the most important figures in the history of Hellenic culture. His writings are an essential source of information on Hellenic and Stoic philosophy, much of which was subsequently lost. His importance to the history of theology rests on the fact that he was the first author to write about the Pentateuch based on the writings of the Greek philosophers available to him. His works also reflect his knowledge of the thoughts of the empirical scientists of his time. Otto Kaiser introduces the reader to the life, work and writings of Philo based on the extant works of Philo as well as of many other ancient writers.