"If Socrates died, then either he died when we was living, or when he was dead. But he couldn't have died when he was living, for he was not dead when he was living. But he couldn't have died when he was dead, for when he was dead he had already died. Therefore, Socrates never died."

“It is probable that those who seek after anything whatever, will either find it as they continue the search, will deny that it can be found and confess it to be out of reach, or will go on seeking it. Some have said, accordingly, in regard to the things sought in philosophy, that they have found the truth, while others have declared it impossible to find, and still others continue to seek it. Those who think that they have found it are those who are especially called Dogmatics, as for example, the Schools of Aristotle and Epicurus, the Stoics and some others. Those who have declared it impossible to find are Clitomachus, Carneades, with their respective followers, and other Academicians. Those who still seek it are the Sceptics. It appears therefore, reasonable to conclude that the three principal kinds of philosophy are the Dogmatic, the Academic, and the Sceptic.”

“Full text of Pyrrhonic Sketches online”