(a) The first problem with the designation of supernatural (or any equivalent term) is that it tells us nothing positive about a god. “Supernatural” tells us what a god is not—that it is not part of the natural universe—but it does not tell us what a god is. What identifiable characteristics does a god possess? In other words, how will we recognize a god if we run across one? To state that a god is supernatural does not provide us with an answer.
In addition, the entire notion of a supernatural being is incomprehensible. The theist wishes us to conceive of a being exempt from natural law—a being that does not fall within the domain of scientific explanation—but no theist has ever explained how we can conceive of existence other than “natural” existence. “Natural existence” is a redundancy; we have no familiarity with “unnatural” existence, or even a vague notion of what such existence would be like.
Natural law pertains to the presence of regularity in the universe, and, for this reason, it is sometimes referred to as the “uniformity of nature.” Entities behave according to specific causal conditions, and we know that an object will not suddenly disappear or act in an incredible manner without an explanation or causal antecedent. Given the right conditions, an acorn will grow into a tree; it will not mysteriously transform itself into a pumpkin, a snowball, or a theologian. A dog will not sprout wings and breathe fire, a cat will not give birth to an elephant, and a colony of ants will not burst into a chorus of the national anthem.
Natural law is based upon the limited nature of existence. Every entity has a specific nature, specific characteristics, that determine the capacities of that entity. A plant, for example, does not have the capacity to think, and a man does not have the biological capacity for photosynthesis. The capacities, abilities, and potential actions of any existing thing, living or inanimate, are dependent on its characteristics—and since these are always specific and determinate, their resulting capacities are also specific and determinate. The characteristics of an entity determine what an entity can and cannot do; limitations are an integral part of the natural universe, and they constitute the foundation of natural law.
Regularity in nature is the consequence of limitations; entities are limited in terms of their actions. No existing thing can randomly do anything at any time under any conditions. This uniformity in nature permits the systematic study of reality (science) and the formulation of general principles of nature (“laws”) which are used in predicting future states of affairs. While the particular scientific laws will change as man’s knowledge increases, the principle of natural law itself is a constant; it persists as a corollary of existence.
This, in essence, is the meaning of natural existence or natural law. A god, as we have seen, cannot exist within this framework, but according to the theists he must exist nonetheless. This brings us to the considerable problem of how anything can exist as a supernatural being.
If a supernatural being is to be exempt from natural law, it cannot possess specific, determinate characteristics. These attributes would impose limits and these limits would restrict the capacities of this supernatural being. In this case, a supernatural being would be subject to the causal relationships that mark natural existence, which would disqualify it as a god. Therefore, we must somehow conceive of a being without a specific nature, a being that is indeterminate—a being, in other words, that is nothing in particular. But these characteristics (or, more precisely, lack of characteristics) are incompatible with the notion of existence itself.