Socrates
Legendary
Socrates wrote nothing, charged nothing, and claimed to know nothing - yet became the father of Western philosophy by relentlessly asking Athenians questions they could not answer. Sentenced to death for "corrupting the youth," he refused escape and drank the hemlock among his students, arguing philosophy to the last minute.
Raises output in every age you own, and most of all in their own. Every level doubles what they add.
