Cyrene, , approx. 435 - 355 B.C.

He is the Cyrenian founder of the Cyrenian Academy of Philosophy. He came of a wealthy family of Cyrene, and lived around 435-355 BC. Somewhat older than Plato, he first followed Protagoras, whose theory of the senses affected him greatly. Later on he became a student of Socrates, whose teachings however did not change his biotheoretical views. After the death of Socrates he kept on living as a Sophist in Athens among other cities in Greece, and later on he spent some years next to Plato in the palace of Dionysius of Syracuse.

Socrates teachings convinced him that knowledge is only worthy when it succeeds in practical and ethical pursuits.

None of Aristippus' writings has survived. Diogenes the Laertian mentions only the titles of his essays. His academy work was passed on to his homonym grandson by his daughter Arete who was the one to continue her father's work to his academy.

He refuses to deal with nothing other than ethic related problems. That is the reason why we find in this philosopher, ideas of main concern ethics and sentimentality.

Aristippus thinks like Heraclitus and claims that the human body, like all things, is subject to constant change. Due to this change the harmony being the natural state of the body is altered, but this can be corrected. Harmony is pleasure; the lack of it means pain. Emotional situations are related to movement, thus slow and easy movement brings pleasure, hard and rapid movement brings pain. Perfect stillness evokes nothing, no pain nor pleasure. Man deserves only pleasure, so the only purpose of will is pleasure. That is how pleasure and virtue are connected, whatever is pleasant is good, while on the contrary everything that causes pain is evil. Everything out of this dipole should be out of concern.

In the question, what is virtue, he answers without hesitation, "virtue is pleasure" thus becoming the founder of hedonism, similar to the eudemonia of Socrates, however Socrates idea is a momentary feeling, rather than a constant state of peace and healthy soul. He has no concern from where pleasure derives. All pleasures are of the same importance, differing only to their intensity. Material pleasure is more intense yet for a small period while ethical pleasures are constant.

According to Aristippus, virtue is nothing but an intense momentary pleasure, as intense as it gets. For one to reach to such pleasure, prudence is needed, this being the Socratic element in his philosophy, giving knowledge its place as a valuable asset, setting one free of superstition, religiousness and vices and providing him with self confidence and certainty. It is of that certainty that the wise dominate to his surrounding environment, and use it according to his will. This is the profile of the wise man for Aristippus and his students, the man who can benefit from life's beautiful things and the good side of people and situations, without losing control, but keeping it over his vices, without trying to have what one cannot have.

He does not believe in social life, he is an atomist. As the Sophists, he also travels from town to town, living free out of every social and political boundary. He was totally indifferent towards religion, declaring that the wise man should be free of the religious beliefs.