ABSTRACT
In discussing the notions of guide men, who were his predecessors, Aristotle adverts to the logical problems inherent in their dilemmas. The difficulties attendant upon the theories of the Greek physicists was insurmountable until such time as the principles of thought should themselves be established. The sophists had indeed effected a transition from philosophy as cosmology to philosophy as concerning itself with man as a thinking subject; but the character of their pursuit was hardly suited to the task of finding a scientific basis for a theory of knowledge and a science of morals. Socrates and Plato were constrained, indeed, to go counter to observed facts and to maintain that men never act contrary to the knowledge that they have, and that every virtue is a kind of knowledge and every evil a kind of ignorance. This chapter helps to understand the full political implications of Plato's doctrine that virtue is knowledge.
