Protagoras and Gorgias are the most significant of the early sophists. Although philosophy as we understand it was not their chief business, they taught views and methods of argument that have fascinated subsequent philosophers. In their own context they exhibit the spirit of the new learning, the cultural and intellectual revolution of the fifth century B.C. in Greece. This revolution - or, rather, the reaction against it - is illustrated in Aristophanes' comic play, The Clouds, by a character enrolling in a sophistic school in order to learn the “unjust argument.” This, he has heard, can win a jury's favour for the worst of offenders. The syllabus, he finds, involves science as well as rhetoric, both laughable in this satire. What is not laughable is the popular animosity against the school that leads to its incineration (at least one student included), a grim sign of the strong feelings that would later contribute to the death of the man whose name Aristophanes uses for the leader of his imaginary school - Socrates.