Socrates said, "All I know is that I know nothing". What I'm trying to figure out is this: if I know NOTHING, how do I KNOW that I know nothing? It just goes round in circles thus becoming nothing more than a paradox. Would you agree?

I agree that the sentence "All I know is that I know nothing" is paradoxical, or anyway false, since if there is one thing that you know than you can't know that you know nothing since that isn't true. But we can probably avoid the problem by saying instead "All I know is that I know nothing else".

Just to set the record straight. Some such claim is often attributed to Socrates on the basis of his remarks in Plato’s Apology (21a-e), but the claim that he actually makes is much less paradoxical. Socrates reports that his friend Chaerephon went to the oracle at Delphi to ask if any person was wiser than Socrates. The oracle apparently answered, no. After having cross-examined lots of people who had a reputation for wisdom and having discovered as a result that their reputation was undeserved, Socrates drew the following conclusion about the significance of the oracle’s answer: “I am wiser than this man; it is likely that neither of us knows anything worthwhile, but he thinks he knows something when he does not, whereas when I do not know, neither do I think I know; so I am likely to be wiser than he to this small extent, that I do not think I know when I do not know” (Ap. 21d-e).

Can we really defend Socrates here though? (Note: It's early Saturday morning and this is relevant to present fearless wading into rough waters.) He says that he is "likely to be wiser" by virtue of not asserting that he knows something worthwhile. But isn't wisdom knowledge? Doesn't being wiser require knowing a little more? If so, then it seems that Socrates really is saying that he knows that he doesn't know anything worthwhile. (That's the knowledge that makes him just a tad wiser.) And now we're back to worrying whether Socrates' assertion is paradoxical.

I can imagine two responses: (A) one might claim that one's failure to know anything worthwhile isn't itself a worthwhile thing to know (and so Socrates' claim to knowledge doesn't clash with what he claims to know, viz. that he knows nothing worthwhile). Or (B) one might hold that one could be wiser simply by failing to claim knowledge that one doesn't have (so we can make sense of Socrates' claim to being slightly wiser without imputing some paradox-threatening knowledge to him).

About (A): but surely what Socrates knows must be worthwhile for that knowledge to make him a little wiser! And about (B): if I'm wise to the degree that I'm failing to claim to know things that are false, then, since there are infinitely many false statements we all fail to claim to know, it's hard to see how anyone's wiser than anyone else.

Time for hasty retreat to shore and coffee.

This dimension of Socrates' thought has been, of course, highly influential with skeptics. Indeed, it was in part on the basis of this sort of gesture in Plato's works that the Academic skeptics regarded themselves as inheritors of Platonic philosophy. Later the idea became known as "learned ignorance," for example in Nicholas of Cusa's work by the same name. It's an interesting thing to examine the different ways philosophers have tried to cope with the constellation of ideas involved with coming to understand one's ignorance, as well as other dimensions of human finitude. Hellenistic and Greco-Roman skeptics explored the ways in which doubt my characterize humanity's relationship to knowlegdge and whether skeptical arguments advance any positive wisdom or simply tear things down. Montaigne formulated the now-classic, "What do I know?" Erasmus called himself a "foolospher." Hume explored concepts of "natural," "common," ordinary, and non-dogmatic forms of belief while still acknowledging skeptical doubt. Wittgenstein in On Certainty and elsewhere considered whether it's even meaningful to speak about not knowing or doubting various locutions; and in a related way Stanley Cavell in The Claim of Reason tries to produce an acknowledgment of the way the deepest way human beings relate to the world is not one of knowledge/knowing. Kiekegaard opted for what he called "indirect" discourse. And perhaps that's the best way of understanding Socrates here--not as trying to state a fact or formulate a proposition but instead to point to or show something important about human wisdom.

Peter is right. Many have taken the Socrates of Plato’s early dialogues to be a skeptic at least with regard to knowledge of the most worthwhile things. My own view is that, at least as he’s represented in the Platonic dialogues, Socrates is not a skeptic. He did not believe that it was impossible to acquire such knowledge. In fact, he devotes his life to acquiring such knowledge. He simply believed that it was very difficult to acquire such knowledge and that no one that he had yet met had done so.

How, then, might he respond to Alex’s worries that his position is paradoxical? He would first have to explain that he could be wiser than someone else without being in a cognitive state that would qualify as knowledge. He would then have to explain that when he speaks of knowledge of worthwhile things, he primarily has in mind knowledge of what things are most worthwhile, that is, what things are the most worthy goals to which we should devote our lives (Ap. 29d-30b). On Socrates’ view, the problem with his fellow Athenians was that they thought that they already knew how they should live their lives. Socrates believed that not only did they have false beliefs about these matters; worse, their belief that they already had knowledge prevented them from being motivated to continue thinking about these matters and eventually getting themselves into a better place. To the extent that he did not believe that he already had knowledge of these important matters, Socrates was one step closer toward achieving knowledge and was thus, to this extent, wiser.

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