A logical problem encountered in Plato's Meno during Socrates' discussion on the acquisition of knowledge.

     "So now I do not know what virtue is; perhaps you knew before you contacted me, but now you are certainly like one who does not know. Nevertheless, I want to examine and seek together with you what it may be.
     "How will you look for it, Socrates, when you do not know at all what it is? How will you aim to search for something you do not know at all? If you should meet with it, how will you know that this is the thing that you did not know?
     "I know what you want to say, Meno. Do you realize what a debater's argument you are bringing up, that a man cannot search either for what he knows or for what he does not know? He cannot search for what he knows - since he knows it, there is no need to search - nor for what he does not know, for he does not know what to look for."1

In this section of the dialogue, the objection raised by Meno relates to the entire definitional search, and it is formally known as Meno's Paradox or The Paradox of Inquiry.

To restate the argument raised :

  1. If you know what you're looking for, inquiry is unnecessary.
  2. If you don't know what you're looking for, inquiry is impossible.
  3. Implicit premise : Either you know what you're looking for or you don't know what you're looking for. This is true iff "you know what you're looking for" is used in the unambiguous sense.

  4. ------------
  5. Hence, inquiry is either unnecessary or impossible.

In looking at the argument as presented in the Meno, the phrase "you know what you're looking for" can be understood in two ways, as there is an equivocation in that phrase.

  • You know the question that you want the answer to.
  • You know the answer to the question you're asking.

In terms of the first sense, the second premise of the argument is true, but the first premise is false. Under the second sense, the first premise of the argument is true, but the second is false. However, there is no one sense in which both of the premises of the argument are true.

So, evaluating the question once again from a different perspective : "Is it possible to know what you don't know?" The answer could be yes or no. In one way, the answer is "no", as you can't know and not know the same thing at the same time. However, the answer could also be "yes", as you can know the questions that you simply don't have the answers to.

Inquiry is possible by grasping the question to which an answer is needed and following correct investigational techniques for answering that question. Knowledge is then aquired in the form of the answer previously unknown to that question. Socrates belives inquiry is possible via the formulation of hypotheses according to true belief and the testing of these hypotheses along with the employment of the elenchus.

Meno's Paradox is thus flawed under the fallacy of equivocation. However, in the dialogue, Meno's Paradox is looked at further in the context of The Theory of Recollection and is therefore not dismissed, but utilized in Plato's further formulation of his epistemology.

1 Plato. Meno. tr. G. M. A. Grube. Stephanus pp. 80 d-e.