Would it make any difference in your evaluation of the coherence of 24+36=60, if you evaluate NOT 24+36=60 first, with a-priori stability? of course it does not, if you understand determinately 24+36=60 , NOT 24+36=60 will appear to you clearly incoherent.
If you find MGB incoherent, with a-priori stability, that´s fine, but, as I think I showed it is impossible that then you find MGB coherent, at that same level of determinate understanding of a MGB or better.
I am not arguing, at the moment, for either way, merely making clear, that claims of any specific person of finding both MGB coherent and incoherent are rather evidence of poor cognition.
If as I seem to interpret you saying, coherence of MGB negates the coherence of ~MGB, it seems what you are suggesting is that the MOA can be boiled down further to;
1) MGB is coherent
2) therefore its negation ~MGB is incoherent, and thus impossible
4) therefore MGB exists
This would mean one doesn't even need to show that MGB is possible, just coherent. Are you suggesting this is the case?
No, that´s not what I am saying, you are getting ahead of yourself, all I have been talking about has been the epistemic situation, when it comes to supporting the possibility premise.
My focus has been completely on how the evidence in favor or against of the possibility premise of the argument works.
There is a larger process in the evaluation of the argument, but, focusing on the conclusion instead on the more specific and localized issue of supporting the premise, as you seem to be doing, runs the risk of begging the question.
There is a BIG difference between :
1. it is possible that maximal greatness is co-exemplified
2. if it is possible that maximal greatness is co-exemplified then maximal greatness is co-exemplified in the actual world.
3. maximal greatness is co-exemplified in the actual world.
Support:
the 2nd premise is true on the basis of axiom 5 of the modal system S5
and, the 1st premise depends on the modal epistemic support, provided for it(e.g. if the concept of maximal greatness coherent? ,etc...).
And then: We find that understood determinately with a-priori stability, the concept of maximal greatness is coherent.
Then, we have good evidence that supports the 1st premise
Finally: If we have good evidence to support the 1st premise (and the 2nd premise is established through axiom 5 of system S5) , and, there is no other outstanding evidence against it, then, we have good reason to accept the the conclusion.
This is roughly correct
And
1) MGB is coherent
2) therefore its negation ~MGB is incoherent, and thus impossible
4) therefore MGB exists
This is completely fallacious.
Now, that this is clear. let´s go back to the matter at hand.
As we have seen
K1: one individual, I1, can find the concept of maximal greatness incoherent, while understanding it determinately, with a-priori stability, but, this implies that if so, this same person will not find the concept of maximal greatness coherent, while understanding it determinately, with a-priori stability.
OR Viceversa.
K2: one individual, I1 , can find the concept of maximal greatness coherent, while understanding it determinately, with a-priori stability, but, this implies that if so, this same person will not find the concept of maximal greatness incoherent, while understanding it determinately, with a-priori stability.
Either K1 or K2 not both can be the case.
If it should happen that (~K) if a person, I1, finds the concept of maximal greatness incoherent and the same person finds the concept of maximal greateness coherent, it is not while understanding the concept of maximal greatness determinately nor with a-priori stability, and, this is not evidence in favor nor against the possibility of maximal greatness being co-exemplified, but, evidence that the person, I1, is in a non good enough cognitive sitution, or does not understand sufficiently the concept of a maximal greatness, or both, and, should refrain from reaching a conclusion either way, and, others should not give any weight in favor or against the possibility premise on the basis of I´s conclusions.
And, to evaluate correctly the coherence or incoherence of maximal greatness, the individual will need to better his cognitive situation, enlarge his relavent conceptual repertoire, as to improve the quality of his relevant cognition and the quantity of his relevant (categorial ) cognition, and then add further relevant specific (non-categorial ) information to his structure of beliefs, to be able to understand determinately , with a -priori stability, while holding that either Maximal greatness is coherent (or incoherent - exclusivey)
I think, this much is clear, now.