Very rough draft: First pass.
A standard distinction between physicalism and supernaturalism/mentalism goes like this:
Physicalism is the view that the physical is fundamental -- everything is either physical or dependent upon/grounded in the physical. By contrast supernaturalism/mentalism is the view that one or more spiritual/mental/supernatural beings are more fundamental than the physical -- everything is either mental or dependent upon the mental.
I have at least two worries for this way of carving things up. I've gestured to the first of these on previous occasions -- viz., that the characterization of the distinction presupposes metaphysical foundationalism, and yet metaphysical foundationalism has recently been called into doubt (on both philosophical and scientific grounds), and metaphysical coherentism and metaphysical infinitism have both recently been vigorously defended.
My second worry is the one I want to briefly focus on in this post. The worry is that it fails to get at what is potentially a deeper distinction, and one that's potentially more illuminating than the distinction between physicalism and supernaturalism. The distinction I have in mind is at the level of basic ontological categories and categorical priority -- in particular, the level of the ontological priority of the categories of substance and property. According to a standard and historically prominent view, substances are more fundamental than properties (or at least: substances are no less fundamental than properties). Accordingly, let's call this sort of view a substance-first ontology.
By contrast, a number of philosophers (e.g., Laurie Paul and Shamik Dasgupa)--due in large part to the growing support for ontic structural realism in the philosophy of physics--have recently argued that properties (or n-ary relations) are more fundamental than substances, and indeed that substances may not even exist. Let's call this sort of view a property-first ontology.
Which view is correct: the substance-first view or the property-first view? This question has potentially huge implications for the disagreement between theists and non-theists.[1] This is because, prima facie, orthodox monotheism entails the substance-first view. And this in turn is because, prima facie, God is a substance, and is prior to all else that exists. Therefore, if there are reasons to prefer the property-first view, then there are thereby reasons to prefer non-theism to theism.
Another way in which the issue has potentially huge implications for theism will take me longer to spell out--certainly not here and now--, but my sense is that is that if properties are more fundamental than substances, then a number of issues related to dualism vs. materialism topic seem to lose much of their force and motivation. For one: there seems no antecedent reason to think there should be just physical properties or just mental properties, and so no antecedent reason to think properties of both sorts can't be fundamental. Another: Some (e.g., Swinburne) argue that theism is simpler than naturalism because it can explain the existence of the natural world, and in a way that is simple (e.g., a single immaterial substance). But on the property-first view, you can be a naturalist that says their ontology is simpler than that of the theist, in that former has a one-category ontology of properties, while the theist starts with a more complex one of substances and properties. (I sketch how this might go here and here).
Another way in which the issue has potentially huge implications for theism will take me longer to spell out--certainly not here and now--, but my sense is that is that if properties are more fundamental than substances, then a number of issues related to dualism vs. materialism topic seem to lose much of their force and motivation. For one: there seems no antecedent reason to think there should be just physical properties or just mental properties, and so no antecedent reason to think properties of both sorts can't be fundamental. Another: Some (e.g., Swinburne) argue that theism is simpler than naturalism because it can explain the existence of the natural world, and in a way that is simple (e.g., a single immaterial substance). But on the property-first view, you can be a naturalist that says their ontology is simpler than that of the theist, in that former has a one-category ontology of properties, while the theist starts with a more complex one of substances and properties. (I sketch how this might go here and here).
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[1] There are other views that are equally powerful threats to theism, one of which is that of ontic structural realism gestured to above, which is a species of the property-first view, but restricted to specifically mathematical structure as fundamental. Another is the stuff-first view, according to which stuffs are more fundamental than substances. Yet another is Jason Turner's facts-first view (as well as related events-first ontologies, such as that presupposed by the GRWf interpretation of quantum mechanics). However, I leave these sort of threats to the side for the present post.
