I think we need to explore the meaning of "subjective truth" first.
There is much controversy surrounding the meaning of "truth" so I'll try and avoid as much of it as possible by first focusing upon what is generally agreed upon. One attribute of truth is that it is itself an attribute, in this case, of propositions. Facts, arguments, evidence cannot be meaningfully evaluated in terms of truth, only propositions.
The next question to ask: "Is truth a primary or secondary attribute?" A primary attribute is one that is inherent in the object (in this case a proposition) whereas a secondary attribute is created by the interaction of the object with a subject.
For example, the property of red paper to reflect and absorb certain frequencies of light would be a primary attribute since this appears to be the same regardless of who is observing it. However, the colour "red" is a secondary attribute since it is dependent on how the sight sense of the observer is tuned to interpret it. Secondary attributes exist because we experience them. It then follows that we can be mistaken in asserting primary attributes but we cannot be mistaken in asserting secondary attributes.
Therefore, if truth is a primary attribute of propositions then this means that a proposition's truth value is independent of who is observing it. If truth is a secondary attribute then a proposition's truth value will vary according to the observer.
I am not clear on the distinction between a primary and secondary attribute. Both your examples rely on observation in order to be attributed. We observe frequencies of light being absorbed by or reflected from a surface. That action is for us an experience of observing the absorption or reflection of light, and so just as dependent upon "how the observer is tuned to interpret it."
Is the distinction you are making then that the primary attribute is assigned by the mutual accord of observers, minimizing individual variations to arrive at a more generalized truth? Or were you maybe leaning toward a distinction whereby the primary attribute is entirely ideal in form, and the secondary attribute experiential? Or both?
Beliefs are propositions that are held by a subject. Propositions themselves are simply statements whose contents are being asserted and so in holding a belief, the subject is asserting the content of that belief. By Moore's paradox, asserting a belief is equivalent to believing it to be true. Therefore, it is clear that a person can only assert a false belief if they are under the mistaken assumption that it is true and, also, this is a scenario that we have all experienced.
Ah, like the belief that the earth is flat, which is only true experientially. Ideally, the earth is round(ish). Both are true, but either is "false" if taken in the context of the other; and since the favoured obsevation is the one of mutual accord, the personal observation is held aloft as unreliable. I see.
(By the way, Moore's Paradox depends on, but does not result in, the proposition you state.)
Therefore, it also follows that truth cannot be a secondary attribute since we are able to be mistaken about the truth of a proposition.
But we could also be mistaken by mutual accord.
If truth is a primary attribute of a propositions then it cannot be subjective and there must be objective truth for all propositions regardless of whether we are sufficiently equipped to discover it.
Now you're taking about the ideal, again --that is, the attribute that exists for us only in the form of an idea, something we reason to exist, something we have to imagine in order to "see," because once we do see it, with our own eyes, it becomes a part of the unreliable.
Can you (ideally) see that you hold the imagined aloft as a "greater truth" than what's infront of your nose? Some atheist you are.
If you reject this line of reasoning then "truth" must be a secondary quality. In this case, we can never be mistaken in asserting a proposition to be true (a proposition is made true in virtue of us thinking that it is true). Therefore, "truth" becomes logically equivalent to "belief" and when we say "X is true" we are saying nothing more than "I believe X".
This is fine but it seems unintuitive. Why not just say "belief" for "belief" and "truth" for "ultimate truth". If you don't believe "ultimate truth" exists then "truth" doesn't exist. It doesn't follow that "truth" is subjective or that we need to create the term "ultimate truth" nor replace "belief" with "truth".
Myself, I don't hold that there is an "ultimate truth" different from "truth." And for the purposes of this discussion, no different than "belief." But I would distinguish between "a belief," which is a proposition, and "belief" that is an act ("to believe"). In belief, the act, we know truth...
"We
know truth." It's that "knowing" bit that people get hung up on. That, and comparing ourselves to others to find a "greater truth" than ourselves.
If I say I believe something, it is (as suggested earlier) the equivalent of it being "true to me." The reason that I believe it, whatever "it" is, is
because I have assigned the attribute "truth" to it --"belief" expresses a relationship I hold with it, one of "it is true to me." So similarly, when I say a thing is true, I can only mean "true to me." An
attribute of a thing is a relationship drawn between a thing and one of its parts; we are the ones who draw those relationships through observation of the world around us. "Truth," as an attribute, is what solidifies what we know into certainty; it's opposite, falsehood, dissolves what we know and leads us to doubt.
We cannot, and should not, remove man from the picture; he is "the observer" of all that he knows, even what goes on in his mind. Still, he removes himself imaginatively, and builds in his mind a world "independent" of what he knows, a world where his contribution doesn't have to matter, where everything is on a level playing field, of equal importance, weight and significance. He attributes "objectivity" to this ideal world.
This sort of reasoning, that holds the truth to be "objective" subjectively assigned, is what seems intuitively correct to me.
(PS I'd frubal you again, but you'll have to wait a bit.)
