It’s the central thesis of all the books my article discusses.

There is more here and (by critiquing it) here.

This idea being: There is a case I believe that it resembles most Syriac Christianity, and likely primitive heretical forms. Indeed Islam may be a survivor of the original Nazorian (Torah-observant) sect of Christians in the general area of northwest Arabia.

Do you remember where you read this idea?

If the class is too small, it can’t be used. And if there are large enough classes to be usable, you have to choose the class that prevails in the Rule of Greater knowledge (as explaining in Proving History). So there is work to be done even to identify the most applicable class. And that isn’t work I can do. I don’t have chops in medieval Arabic history and languages. So there is no way for me to construct a prior. Only experts in the subject can.

I don’t see why a narrower class would be helpful in this case, except if we narrow it down by time or the type of sources available for the person which would be legitimate. So for eg, pre-1500 prophets, or the set of prophet claimants who are attested in historical records 10-15 years after their death in tradition. Is that something like what you meant? I guess the ideal situation is to stack as many traits and come up with 6+ members for a class? But if we are to add something like Abrahamic religion prophet claimant as a trait, I don’t really see how would that be relevant.

Mohammed belongs in the class of people who claimed visions from a deity

That doesn’t quite work, since everyone belongs to thousands of reference classes. The most constrictive class is the only relevant one. I explain this in OHJ, Ch. 6, “Alternative Class Objection,” with examples.

what does “nearest comparables on both sides” mean?

Both sides of the argument, e.g. people in-class who didn’t exist and who did. You can’t cherry pick the set. They all go in.

It seems to me thay the prior odds must be high, since Mohammed belongs in the class of people who claimed visions from a deity, and which has a high % of people who are historical, but in any case, what does “nearest comparables on both sides” mean? I haven’t read all your works so I don’t know where/if you cover what that means.

I don’t know enough about medieval Arabic history and literature and language to answer these questions. That is the point of the article you are commenting on. I’m not the guy who can do this. You need someone with a PhD in medieval Arabic literature.

In general methodological terms though: in the absence of local referents (e.g. if the set of referents in Arabia circa 600 AD contains only one member; I do not know if that’s the case, I am just saying, if it should be), then the next most applicable reference class is the nearest constructable class (I discuss this in chapter six of Proving History).

And that class must contain all referents not just ones supporting the conclusion. So, for example, if Joseph Smith goes in, then John Frum, Tom Navy, Ned Ludd, and Haile Selassie might go in the set too. I don’t know. One would have to find the nearest comparables on both sides to build a set, usually of at least six members for statistical relevance to attach. And failing that, you can just set the prior at 50/50, representing the absence of any prior or applicable comparables. That would quantify the condition whereby, apart from evidence specific to Mohammed and Islam, there is no information at all that makes his existence more likely or less. Which translates mathematically into P = 0.5.

Probably. I have not looked into that. But be aware, the Quran appears to have more in common with apocryphal traditions rather than canonical. So it’s not really a question of which “of the four” Gospels because the answer then is zero.

There is a case I believe that it resembles most Syriac Christianity, and likely primitive heretical forms. Indeed Islam may be a survivor of the original Nazorian (Torah-observant) sect of Christians in the general area of northwest Arabia.

As for the rest, I don’t know. Medieval Arabic studies is not my area.