After the death of Socrates there arose several schools professing to be founded upon his principles. The divergences they exhibited when compared with one another prove how little there was of precision in those principles. Among these imitators is numbered Euclid of Megara, who had been in the habit of incurring considerable personal risk for the sake of listening to the great teacher, it being a capital offence for a native of Megara to be found in Athens. Upon their persecution, Plato and other disciples of Socrates fled to Euclid, and were well received by him. His system was a mixture of the Eleatic and Socratic, the ethical preponderating in his doctrine. He maintained the existence of one Being, the Good, having various aspects--Wisdom, God, Reason, and showed an inclination to the tendency afterward fully developed by the Cynical school in his dogma that the wise man should be insensible to pain. [Sidenote: The Cyrenaic school. Pleasure is the object of life.] With the Megaric school is usually classified the Cyrenaic founded by Aristippus. Like Socrates, he held in disdain physical speculations, and directed his attention to the moral. In his opinion, happiness consists in pleasure; and, indeed, he recognized in pleasure and pain the criteria of external things. He denied that we can know anything with certainty, our senses being so liable to deceive us; but, though we may not perceive things truly, it is true that we perceive. With the Cyrenaic school, pleasure was the great end and object of life. [Sidenote: The Cynical school: a contempt for others and gratification of self.] [Sidenote: Antisthenes.]