“I appear to be wiser than he, because I do not fancy I know what I do not know.”
I am wiser than this man, for neither of us appears to know anything great and good; but he fancies he knows something, although he knows nothing; whereas I, as I do not know anything, so I do not fancy I do. In this trifling particular, then, I appear to be wiser than he, because I do not fancy I know what I do not know.
—attributed to Socrates, from Plato, Apology, psychology, Dunning-Kruger effect
Art of Quotation 