4.08.2006

Cohen's Paradox

Help me out by letting me know your intuitions regarding the following case.
When is the following sentence truthfully uttered and when is it not:

Joe is on the witness stand at a trial and utters the following:

U: "I state that I have never been a member of the communist party."

Now when is what he says true? Here are some options:
(i) U is true in virtue of Joe saying it.
EVIDENCE: Since U is about what is stated, and Joe is stating what he is reporting himself to be stating, U is true. Compare if Joe said, "Mary states that I have never been a member of the communist party." Joe would be speaking truthfully regarding Mary solely based upon the things that Mary states -- it would have nothing to do with Joe's actual membership of the communist party. Since the sentence about Mary has a similar structure to U, U should be treated in the same way, thus it is true if and only if Joe states it. Since Joe does state it, U is true.

(ii) U is true in virtue of whether or not Joe has ever been a member of the communist party. If he has, then U is false, if he has not, then U is true.
EVIDENCE: The judge would not be happy if he later found out that Joe was merely reporting what he states, not anything about his political memberships. Joe would likely be convicted of perjury if he had been a member of the communist party.

(iii) U is true if and only if Joe states it and he has never been a member of the communist party.
EVIDENCE: Conjoin the evidence for (i) and (ii), both are good, but neither is sufficient.

(iv) U is true if and only if some other reason.
EVIDENCE: You tell me.

2 comments:

Trent Steele said...

I'd say the expression as such has no truth value. Rather, I'd say the statement as uttered relative to a context may have a truth-value.

For instance, if Joe says U after having been asked, "What is your statement regarding your involvement with the communist party?" I think it's pretty clear that U is true by virtue of Joe's having said it (his utterance is the truth-maker), assuming that U is Joe's original statement (that is, that U isn't uttered at some time subsequent to Joe's having made a contrary statement about his involvement with the communist party).

However, if the eliciting question is something like, "Joe, have you ever been a member of the communist party," the question becomes interesting. In this case, there seems to be a "literal" sense in which Joe tells the truth in his utterance of U, but Joe's intention would clearly be to mislead his interlocutor. The conversational implicature of U in this case seems to be:

U': I have never been a member of the communist party.

Now clearly U' is truth-evaluable by virtue of your criterion (ii), but U still is not. So, in this latter case, I'd say Joe's utterance of U can still express a truth, but it may or may not be the truth Joe intends to express.

Those are my first thoughts, anyway.

jon said...

Trent, I initially shared your intuitions. Except I do think that Joe's statement would be true even if he had uttered a contrary statement prior. There is no contradiction in uttering contradictory things. I am also not sure how the context sensitivity is going to work. Besides "I" it is hard to see what would make U's truth value dependent upon context.

I now think that something like (iii) is the right route of response. The idea is that when Joe utters U he actually expresses more than one proposition. For instance he expresses:
p: [Joe, stating Joe's not a member]
p': [[Joe, being a member]NEG]
and perhaps others as well.
Multiple propositions are often expressed by the same sentence, the problem here is just that the multiple propositions have radically different truth conditions.

Taken this way, for U to be true - where true means expressing only true propositions - then we would need to appeal to (iii).

I think this gives us the answer we want in a reasonable way.