This study proposes that Neoplatonism, while not a modern philosophy, is philosophy in the modern sense. Lloyd analyzes the key structures that underlie the dogmas of the Neoplatonic world picture, including the concept of emanation, the return of the soul to the One, the place of mystical knowledge, epistemology, and Porphyry's theory of predication, and shows that they rest on original but intelligible concepts and arguments.