As Athens grew in influence, it attracted more and more people from other city-states and countries. Opportunities for a growing number of Athenians to speak before the Assembly created a demand for specialized education in subjects such as letters, rhetoric, science, statesmanship, and philosophy. Those who considered themselves as original, true Athenians became increasingly ethnocentric. The sophists were the first true professional educators, a group of wandering teachers who charged a fee to teach anyone who wished to study with them. They taught that truth is relative and that knowledge is determined by specific qualities of the observer.
Protagoras of Abdera was one of the most influential of the Sophists. Protagoras was an exemplary sophist. He was an active traveler and first-rate observer of other cultures who noted that although there are a variety of customs and beliefs, each culture believes automatically that its own ways are right and outright condemns views that differ from its own.
He said that morals are nothing more than the social traditions, or mores, of a society or group and that following local mores is the best way to live successfully and well, in that place. Therefore his famous remark: Man is the measure of all things.
Of all the Sophists, Socrates was my favorite. He was the first major Western philosopher who wrote no philosophy. What we know about him comes from his pupils, Plato and Xenophon. Socrates challenged the Sophist doctrines of relativism, moral realism, and might makes right. He also believed that if anyone took money for teaching, then they could not teach the truth. Socrates perfected a style of philosophical inquiry know as the Socratic Method or dialectic. Based on the assumption that the purpose of education is to draw the truth out of the pupil rather than "fill an...