The matters I address here serve as a response to many arguments which base themselves on claims of the supernatural or God being more probable explanations of reality.
First, all things that cause, affect, or interact with other things are part of a single system of causation with the things they cause, affect, and interact with. It is incoherent to say otherwise.
Mechanistic Systems of Behavior
Second, it is conceptually incoherent to imagine that anything is exempt from operating by some “rules” of behavior. These may be fully mechanistic or capable of yielding a degree of randomness (although note that even quantum mechanics exhibits probabilities in behavior that can be precisely calculated, which thus cannot be pure randomness), but I can conceive of no exemption from these categories.
In regard to what we consider physical matter, we call these rules “physics”. But without a system of rules that determine the nature of an entity or phenomena, it is incoherent to suppose that anything would continue to exist or be what it is. A definition of anything and its nature necessarily refers to a description of behaviors of the parts and whole of any system or entity. Such rules are ultimately what make anything distinct and definable. Without such rules, then we cannot define anything, and we can only be talking about the concept of nothingness (i.e. non-existence).
So we need to accept that anything that can conceivably exist in any manner must be operating by a system of behavior, and thus we must recognize that all entities and phenomena are subject to – or perhaps rather, defined by – systems of behavior.
Consider that when we speak of a tree, for example, everything we mention about it ultimately has basis in how the parts and forces operate that constitute a tree, and which includes that its most fundamental parts exist at all or that the manner in which they exist (such as if physical material is illusory) occurs.
The implications of these propositions are manyfold.
The “natural” versus “supernatural” distinction is nonsensical because whatever exists shares the same nature of being defined by mechanistic or partially random causation, and interacting with other components of the total system.
Thus, arguments that appeal to “supernatural” entities and forces that are allegedly separate and exempt from the mechanistic way that nature works in order to explain nature in fact offer no explanatory power.
Whatever they hypothesize would have to be part of the single unified system of nature itself, so any crucial properties or causal source can really only be considered part of the natural world. And this eliminates any usefulness for concepts like souls and spirit beings that are based upon the idea that mechanical rules cannot explain things like sentience or the existence of the natural world; for we realize that they amount to meaningless additional steps and components that often raise more questions than they answer. Then on top of that, arbitrary mythology is needed to describe the way these entities are formed, what happens to them and why, and so on.
So the label of “supernaturalism” is merely used to imply that these ideas (of “spirit”, etc) describe a unique explanation that they do not actually provide. For example, ideas such as the notion of being eternal or timeless can, and logically must, apply to some component of the natural world itself, or perhaps the entire cosmos.
Also, all changes and occurrences are thus internal changes, not separate distinct links in a linear chain of causation. To use one example, it is the internal changes occurring within a single system that transforms a rock into an ax head; in reality, there is no outside actor that shapes the rock independently of the rock.
Sentience (or consciousness) also lacks explanatory power as a causal factor because, due to the points made thus far, it too must be, or directly derive from, a sort of mechanistic natural system. And elsewhere I have addressed in detail how the concept of Free Will is nonsensical and our thoughts must conform to mechanistic behavior. This is not to declare that the cosmos must be unconscious or that some form of panpsychism is false, but it informs us that we have no rational basis for developing explanations based upon it.
Any being, whether you call it a god or anything else, would just be a self aware part of reality or possibly a word for whole system of reality. But the notion of any being as unique causal factor offers no explanatory power. The question is simply whether or not anything likely exists that would match our definition of a particular being, like a “god”.
Given the points raised thus far, we can consider that whatever existed prior to the current state of the cosmos as we perceive it, must have always inherently possessed the requisite capability to mechanistically result in the universe we have today; and furthermore, it need only be sufficient for this purpose, not greater.
This means that if a creative designer being existed, then that being was inherently already a system or entity in a state that could mechanistically produce the universe we now have. But this hypothesis would be no different than saying that some other aspect or structure of nature itself was in such order, so the hypothesis of creation by cosmic intelligence is just built upon numerous unnecessary assumptions and is unfounded.