The saying γνῶθι σαυτόν ("know thyself") was prominently displayed at the temple of Delphi, where ancient Greeks, Romans, Persians, and others sought answers to their most pressing questions. Yet what is it exactly to know thyself? Essential clues can be found in an obscure little book published in 1916: "Know Thyself" in Greek and Latin Literature, in which Eliza Gregory Wilkins collected almost all mentions of the maxim up until the fall of Rome.
Here are some of the key meanings:
Know your measure and limits. In ancient Greece, well-known examples of people who didn't know their limits were Alcibiades and Alexander the Great; the latter in particular had the hubris to think that he was a god. Less exceptional citizens might over-estimate their power, their status, their influence, the loyalty of their friends, the stability of their wealth, and so on.
Know what you can and cannot do. This sense, which implies neither over-estimating nor under-estimating your abilities, is well illustrated by the myth of Icarus trying, impossibly, to fly to the sun. A more prosaic example is that of the Sophistic teachers, who claimed superior abilities to impart wisdom but in fact lacked such skills.
Know your place. Here "know thyself" verges on the virtue of moderation or self-regulation (σωφροσύνη): someone who was ignorant of his place was liable inappropriately engage in wild, immoderate, self-indulgent behavior.
Know the limits of your knowledge and wisdom. Consider, for example, that Alcibiades (in his eponymous dialogue) thought he was ready to take a leading part in the public affairs of Athens even though he was only 20 years old. Indeed, throughout the Socratic dialogues of both Plato and Xenophon, Socrates delights in exposing the pretensions of those who claim to know more than they really do.
Know your faults. As Aristotle says in the Magna Moralia, because we don't know ourselves we tend to criticize others for the very same faults that we ourselves have; one of the benefits of having close personal relationships is that our friends and relations might feel free to point out our failings even when we don't want to own up to them.
Know you are human and mortal. This sense was often expressed by the idea that you should stay aware that you will die eventually, with the result that you might savor your mortal existence. A related aspect was often expressed by the maxim that "one who is human should think mortal thoughts" and therefore not reach for the divine.
Know your soul. In tension with that last thought, knowing your soul could involve a recognition of the soul's divine origin or nature, as in Plato's Phaedo or book ten of Aristotle's Nicomachean Ethics. Alternatively, it could involve awareness of the conflicting drives experienced by human beings, so that you could achieve greater internal harmony. Or consider Aristotle's repeated statement that we are social animals and thus need to understand interpersonal relationships in order to thrive in society.
The astute reader will have noticed that one meaning conspicuously absent in ancient times was the very one we especially treasure nowadays: knowing your singular uniqueness, discovering your true self, cherishing your individuality, and the like. I'll have more to say on this score in a future post.
(Cross-posted at philosopher.coach.)
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