Moore's Paradox - The Problem

The Problem

Since Jaakko Hintikka's seminal treatment of the problem, it has become standard to present Moore's Paradox as explaining why it is absurd to assert sentences that have the logical form: (OM) P and NOT(I believe that P), or (COM) P and I believe that NOT-P. Commentators nowadays refer to these, respectively, as the omissive and commissive versions of Moore's Paradox, a distinction according to the scope of the negation in the apparent assertion of a lack of belief ('I don't believe that p') or belief that NOT-P. The terms pertain to the kind of doxastic error (i.e. error of belief) that one is subject to, or guilty of, if one is as the Moorean sentence says one is.

Moore himself presented the problem in two ways.

The first more fundamental way of setting the problem up starts from the following three premises:

1. It can be true at a particular time both that P, and that I do not believe that P.
2. I can assert or believe one of the two at a particular time.
3. It is absurd to assert or believe both of them at the same time.

I can assert that it is raining at a particular time. I can assert that I don't believe that it is raining at a particular time. If I say both at the same time, I am saying or doing something absurd. But the content of what I say—the proposition the sentence expresses—is perfectly consistent: it may well be raining and I may not believe it. So why can't I assert that it is so?

Moore presents the problem in a second, distinct, way:

1. It is not absurd to assert the past-tense counterpart, e.g. 'It was raining but I did not believe that it was raining'.
2. It is not absurd to assert the second- or third-person counterparts to Moore's sentences, e.g. 'It is raining but you do not believe that it is raining', or 'Michael is dead but they do not believe that he is'.
3. It is absurd to assert the present-tense 'It is raining and I don't believe that it is raining'.

I can assert that I was a certain way (e.g. believing it was raining when it wasn't), that you, he, or they, are that way, but not that I am that way. Why not?

Many commentators—though by no means all—also hold that Moore's Paradox arises not only at the level of assertion but also at the level of belief. Interestingly imagining someone who believes an instance of a Moorean sentence is tantamount to considering an agent who is subject to, or engaging in, self-deception (at least on one standard way of describing it).