One way of understanding “science” is that it is concerned with the discovery and verification of facts. But, what is a “fact”? The word “fact” has different meanings or shades of meaning, depending on what it is that we are contrasting with “fact”. One important distinction is that of fact vs. theory.

D. Fact vs. Theory

What I have in mind here is the idea that direct observations are where the rubber meets the road in science. Theories can be tweaked, revised, and even rejected, but “facts” or direct observations are not so easily adjusted or rejected.

This distinction is clearly of importance, but it cannot be used directly to distinguish between science and non-science, because science definitely involves both observational claims and theoretical claims. In Rocks of Ages, Stephen Gould briefly describes science:

Science tries to document the factual character of the natural world, and to develop theories that coordinate and explain these facts. (ROA, p.4)

…the net, or magisterium, of science covers the empirical realm: what is the universe made of (fact) and why does it work this way (theory). (ROA, p.6)

What we want most from science is true theories about how the world operates, not just true observations about things and events in the world. So, we cannot define science as being limited only to the discovery and verification of observational claims or to just “facts” as opposed to theories.

The question of the existence of “God” would seem to be more a theoretical issue than one resolvable by direct observation. This is in part because God is supposed to be a spirit, a bodiless person. Given this conception of God, we cannot expect to see, hear, touch, smell or taste God, at least not in any literal way.

Furthermore, philosophical arguments have been offered for and against the existence of God, so it would seem that such arguments need to be examined and taken into consideration. Even the rejection of all philosophical attempts to determine the truth of this matter will, presumably, be based on some sort of theory about the nature of philosophical inquiry and about the epistemology of religious beliefs.

Arguments for and against the existence of God are based on empirical facts or generalizations. So, the existence of God can be viewed as a theory that is an attempt to explain various facts or observations.

Since science encompasses both observational claims and theories that attempt to explain the observations, we cannot remove the existence of God from the scope of scientific inquiry on the basis of the view that the question “Does God exist?” is a theoretical question, rather than one that can be resolved directly by observation.

But is the claim that “God exists” a scientific theory? According to Richard Swinburne, scientific explanations must be distinguished from personal explanations and in empirically-based arguments for the existence of God, it is a personal explanation that is being given for the phenomena. Swinburne also argues that personal explanation cannot be reduced to scientific explanation. So, if the claim that “God exists” is put forward as a personal explanation for empirical facts or generalizations, then this is not being put forward as a scientific explanation.

If the claim “God exists” is not being put forward as a scientific explanation for empircal facts and generalizations, but is instead being put forward as a personal explanation for empirical facts and generalizations, then this might be a good reason for concluding that “God exists” is not a scientific theory or hypothesis.

So, here is a possible line of reasoning for the view that the issue of the existence of God is not a scientific question:

1. The claim “God exists” is being put forward as a personal explanation for empirical facts and generalizations, and not as a scientific explanation for empirical facts and generalizations.
2. If the claim “God exists” is being put forward as a personal explanation for empirical facts and generalizations, and not as a scientific explanation for empirical facts and generalizations, then the claim “God exists” is not a scientific theory or hypothesis.
3. If the claim “God exists” is not a scientific theory or hypothesis, then the question “Does God exist?” is not a scientific question.
Therefore:
4. The question “Does God exist?” is not a scientific question.
I don’t know if this is a sound argument, but it does seem to be one worth thinking about.
One weakness of this argument is that it seems to be dependent on the particular historical circumstances of the types of arguments that have been given in the past for the existence of God.
Even if all of the traditional arguments for God are indeed in the form of personal explanations, it still seems possible that some new argument could be constructed in the future that would be radically different and instead be in the form of a scientific explanation. For this argument to be persuasive, one would need to have some reason to believe that this possibility is either extremely unlikely or just not possible.