I think you've both highlighted the initial problem though, which is P1 here
↪Bob Ross
. It seems entirely possible that a belief could be related to the truth value of some proposition.
Do you think that a stance about the trueness or falseness of something, is independent of the trueness or falseness of something?
I think we have to be very careful here, because I don’t disagree that a “belief could be related to the truth-value of a proposition” in the sense that I think you mean it. “I believe tacos taste good” is a proposition and part of what it references relates to a belief (in this case, a belief
about tacos), but this is not the same thing as saying that a proposition’s truth-value is relative to a belief.
For example, “1 + 1 = 2” is a mathematical proposition of which its truth-value is clearly not relative to a belief; however,
the same is the case for the non-mathematical proposition “I believe 1 + 1 = 2”...it is just harder to spot. The truth-value of “I believe 1 + 1 = 2” is
not relative to any stance: either the subject believes it or they do not—irregardless of their stance on the proposition “I believe 1 + 1 = 2”. The “truthity” of “I believe 1 + 1 = 2” is stance-independent.
Why, then, do so many people, including yourself, say it is not? Because, of course, to evaluate the truth-value of the proposition “I believe 1 + 1 = 2” one must evaluate the belief of some subject; and, in this sense, one wants to say “the ‘truthity’ of <...> is stance-dependent”.
It is imperative, then, to pinpoint
what the proposition is: when someone, like yourself, says the above, they are thinking of the truth of whether or not what the belief
references is true or false (e.g., “1 + 1 = 2”, “tacos taste good”, etc.) and
not the actual proposition at-hand (e.g., “I believe 1 + 1 = 2”, “I believe tacos taste good”, etc.). They then conflate them, and say that the proposition at-hand is stance-dependent (in terms of its “truthity”) when, really, the part of the content, which may or may not itself be a proposition, has its “truthity” relative to a stance.
We have to dissect this with razor-sharp knives and as elegantly and precisely as a surgeon to avoid this conflation (which I think you are making).
Why is this a big deal, you may say? Because what was originally being accounted for
as propositional by way of relativity to beliefs dissipates with this transformation—e.g., one that argues that “1 + 1 = 2” does
not express something objective
but is propositional because it is relative to a belief, will have to transform it into “I believe 1 + 1 = 2” which loses its original meaning (viz., it is no longer the same proposition, and the one which was denied as objective is not actually propositional: it is, rather, the indexical statement that is).
See what I mean?
When it comes the sort of self-reference at work in the OP though
What self-reference? A stance about something is independent of that something; which does not negate, to your point, that some statements reference subjective dispositions which, in turn, require one to evaluate to determine the truth-value of it (which, again, is not the same thing as the truth-value itself being relative to a subjective disposition: I am cutting ever-so precisely here, or at least trying to, in order to convey the point).
That I have to evaluate the subjective dispositions of a person to determine the truth of something, does not entail that the truth of that something is subjectively determined.