Plato's Theory of Ideas

For it suffices for our purpose that this is, in any case, the figure of Socrates as it was drawn in the soul of his enthusiastic student, who is on the point of becoming his successor (39 CD), and the figure of his teaching, in which it forms the presupposition for his own philosophical development.

According to this account, Socrates absolutely did not wish to be considered a knower of anything, except for the one thing: that he knew precisely this, his own not-knowing. Above all, he confesses his total not-knowing regarding the very central object of his investigation: the moral concepts. He believes that knowledge about this is, in fact, unattainable for human beings in general. In contrast, he claims to possess—and demands unconditionally from everyone—the only knowledge: knowing whether one knows or not. It is the most shameful ignorance to imagine one knows what one does not actually know (29 A).

Socrates does not, therefore, say: "I know nothing of such-and-such objects, for example, what is 'in the sky and under the earth'" (19 B, 23 D), as Xenophon has arranged the master's opinion to fit his own view, but "I do know of what is in our domain." Nor does he say: "I know nothing in general of the connections of external nature, but I do know of the moral, of 'human and civic virtue'" (20 B). Rather, he declares point-blank that he understands nothing of this or that science, and therefore cannot teach anyone anything about it, nor "improve"—that is, advance—anyone in it, nor "educate" people. That may well be a fine art, he declares, but "I do not understand it" (20 C). Whoever claims of me that I lay claim to such things, "lies and speaks to my slander" (20 E, cf. 33 A). He expressly rejects the widespread misunderstanding that his not-knowing is merely an ironic pretense, and that he actually believes himself to know, or wishes to be considered by others as knowing, that which he feigns ignorance of.

How is one to interpret this strange science of not-knowing? Schleiermacher has convincingly explained it through the distinction between the form and the matter of knowledge.

¹ I have expressed my opinion on this in the Philosophische Monatshefte, Vol. 30, p. 337 ff., esp. 348.