After the "The Big Three in Greek Philosophy", Socrates, Plato, and Aristotle, Stoicism became one of the most influential philosophies of the Roman world and has continued to influence many of history’s greatest minds.
The Stoic philosophers (so called because Zeno, the founder of the Stoic school used to teach under a column or "stoa" around 300 BC) believed that the central work of human beings was to live up to their true selves.
Here’s how Seneca, one of the main Stoics, puts it:
"Man’s ideal state is realized when he has fulfilled the purpose for which he is born. And what is it that reason demands of him? Something very easy—that he live in accordance with his own nature."
Marcus Aurelius, another Stoic Philosopher (and Roman Emperor a hundred years after Nero), said something very similar in his classic Meditations: "Everything - a horse, a vine - is created for some duty... For what task, then, were you yourself...