A first approximation to what I want to draw a distinction between is parts of a hypothesis that are correlated with the rest of the parts, and parts that aren’t, so that and adding them decreases the probability of the hypothesis more. In the extreme case, if a part of a hypothesis is logically deduced from the other parts, then it’s perfectly correlated and doesn’t decrease the probability at all.
When we look at a hypothesis, (to simplify, assume that all the parts can be put into groups such that everything within a group has probability 1 conditioned on the other things in the group, and all groups are independent). Usually, we’re going to pick something from each group and say, “These are the fundamentals of my hypothesis, everything else is derived from them”. And see what we can predict when you put them together. For example, Maxwell’s equations are a nice group of things that aren’t really implied by each other, and together, you can make all kinds of interesting predictions by them. You don’t want to penalize electromagnetics for complexity because of all the different forms of the equations you could derive from them. Only for the number of equations there are, and how complicated they are.
The choice within the groups is arbitrary. But pick a thing from each group, and if this is a hypothesis about all reality, then those things are the fundamental nature of reality if your hypothesis is true. Picking a different thing from each group is just naming the fundamental nature of reality differently.
This of course needs tweaking I don’t know how to do for the general case. But...
If your theory is something like, “There are many universes, most of them not fine-tuned for life. Perhaps most that are fine-tuned for life don’t have intelligent life. We have these equations and whatever that predict that. They also predict that some of that intelligent life is going to run simulations, and that the simulated people are going to be much more numerous than the ‘real’ ones, so we’re probably the simulated ones, which means there are mind(s) who constructed our ‘universe’.” And you’ve worked out that that’s what the equations and whatever predict. Then those equations are the fundamental nature of reality, not the simulation overlords, because simulation overlords follow from the equations, and you don’t have to pay a conjunction penalty for every feature of the simulation overlords. Just for every feature of the equations and whatever.
You are allowed to get away with simulation overlords even if you don’t know the exact equations that predict them, and if you haven’t done all the work of making all the predictions with hardcore math, because simulation overlords have a bunch of plausible explanations, how you could derive them from something simple like that, because they are allowed to have causal history. They are allowed to not always have existed. So you can use the “lots of different universes, sometimes they give rise to intelligent life, selection effect on which ones we can observe” magic wand to get experiences of beings in simulations from universes with simple rules.
But Abrahamic and deistic gods are eternal. They have always been minds. Which makes that kind of complexity-reducing correlation impossible (or greatly reduces its strength) for hypotheses with them.
That’s what I was trying to get at. If that’s not what ontologically basic means, well, I don’t think I have any more reason to learn what it means than other philosophical terms I don’t know.
Omniscience and omnipotence are nice and simple, but “morally perfect” is a word that hides a lot of complexity. Complexity comparable to that of a human mind.
I would allow ideal rational agents, as long as their utility functions were simple (Edit: by “allow” I mean they don’t get the very strong prohibition that a human::morally_perfect agent does) , and their relationship to the world was simple (omniscience and omnipotence are a simple relationship to the world). Our world does not appear to be optimized according to a utility function simpler than the equations of physics. And an ideal rational agent with no limitations to its capability is a little bit more complicated than its own utility function. So “just the laws of physics” wins over “agent enforcing the laws of physics.” (Edit: in fact, now that I think of it this way, “universe which follows the rules of moral perfection by itself” wins over “universe which follows the rules of moral perfection because there is an ideal rational agent that makes it do so.”)