You appear to be assuming mathematical platonism? — Michael

No, I'm not assuming mathematical Platonism or anything else.

The proposition "X is a prime number" is assessed as accurate/true when uttered. — Michael

As I said I'm not proposing anything. I just write down a number and ask the question as to its primeness. I know the truth regarding its primeness is prior to even writing the number down and certainly prior to my discovering it. And of course I will have to discover it, most especially in the case of extremely large numbers.

But "a truth" means "a true proposition", and so you are saying "there is a true proposition about whether or not that number is prime; no proposition required". — Michael

You are simply asserting, without supporting argument, that truth is only a property of some propositions. If you open your mind and think about it you will see that my example of prime numbers throws that assumption into question—makes it look like the partial, not the whole truth.

Also, accuracy is not a precisely d;eterminable quality.
— Janus

Then neither is the truth of the proposition "the painting is accurate — Michael

I agree, but it is irrelevant to the question about prime numbers.

If you open your mind and think about it you will see that my example of prime numbers throws that assumption into question — Janus

You seem to be saying that the proposition "X is a prime number" is true or false before it is uttered but denying that this is a case of a proposition being true or false.

I'll try one last time If you won't address what I actually write, there is no point continuing. I haven't uttered any proposition; I've just nominated some extremely large number and asked the question about its primeness. Do you deny that the truth regarding the number's primness is prior to my proposing anything about it, and in fact prior to my even nominating it, or not. If not, why?

- See this exchange and following:

Just as a sentence being true (or false) before it is said makes no sense. — Michael

What are the chances that anyone has ever said that 799168003115 + 193637359638 = 992805362753? — Srap Tasmaner

Right...a very similar point. And yet @Michael remains oblivious it seems...or willfully blind.