by Adam Lee on March 19, 2011

Some of my favorite atheist writers have been jousting over the issue of whether any imaginable evidence could convince them of the existence of God. Among those who answer in the negative, the consensus seems to be that God is such a nebulous and unfalsifiable hypothesis, it’s impossible to test in any meaningful way.

This is a topic I’ve spent some time contemplating myself, and though I think differently than they do, I’m sympathetic to that objection. Despite millennia of cogitation, theologians have never produced a clear and consistent definition of God’s nature and powers.

So, let’s see if we can help them out.

In this essay, I’ll list three different classes of hypothetical beings that could claim the term “god” and consider how each of them differ. I’ll then discuss what we might do if we ever encountered a being that could plausibly claim to belong to one of these categories.

God Type I: The Sufficiently Advanced Alien

The first candidate, and the lowest on the scale of godhood, is the Sufficiently Advanced Alien. This could be an extraterrestrial from a civilization technologically advanced far beyond ours, but it doesn’t have to be. It could be a human-created Singularity-type computer supermind, a time traveler from the far future, a Star Trek-esque energy being, whatever. Its exact nature isn’t important. What matters is that it exists in this universe and is constrained by its physical laws, but can do anything or almost anything that’s theoretically possible under those laws. I could imagine a sufficiently advanced alien that could use sophisticated nanotechnology to cure disease, read our thoughts by mapping patterns of brain activity, control the weather in a small region to strike blasphemers with lightning, and so on, thus acting for all intents and purposes like the gods of old.

I would also count pagan deities like the Greek gods under this category. They were superior to humans in some ways, such as possessing immortality, but they were creatures of this universe and were in some sense subject to its laws.

God Type II: The Chief Programmer

Moving up a step, we come to the Chief Programmer. The conceit here is that there’s another universe, which arises and evolves according to its own set of natural laws (whatever they may be), ultimately giving rise to intelligent life. That life becomes technologically advanced and builds powerful computers, or the equivalent – so powerful that they can simulate, in arbitrarily fine detail, the workings of an entire cosmos – and we are that cosmos. The true nature of our existence is that we’re programs running on a supercomputer operated by a far more advanced civilization, and the simulation is so realistic that we’re unaware of this.

The programmer in charge of the simulation, if it chose to interact with us, would be godlike. It could infallibly predict the future by rewinding time and then replaying it; resurrect the dead by loading their personality from a backup copy; run our universe in a debugger to read people’s thoughts, influence their actions, or alter the course of events in subtle and undetectable ways. It could change the parameters of the program to selectively suspend our natural laws – creating a perpetual motion machine, making force equal something other than mass times acceleration, changing the value of Planck’s constant, or removing the light-speed limit. Any form it could take in our universe would only be an avatar, and even if we disabled or destroyed that, the mind guiding it isn’t part of our universe and wouldn’t be affected.

This is the Chief Programmer: any being that’s a natural entity in its own universe, but functionally omnipotent with respect to ours. The scientists in Stanislaw Lem’s “Non Serviam” were Chief Programmers from the perspective of their artificial beings, as is the protagonist of this xkcd strip. But it doesn’t have to be a computer programmer, per se. We could be figments of the imagination of some superbeing, dreaming a fantastically vast and intricate lucid dream, or characters in a novel being written by an unimaginable Author.

God Type III: The Empyrean

Finally, there’s the category about which there’s the most controversy, a god of the type usually pictured by monotheistic religions. Like the Chief Programmer, it’s fundamentally omnipotent and omniscient from our perspective – able to alter reality at will, powerful enough to achieve anything that isn’t a logical contradiction, and aware of everything that can be known. The difference is that, rather than being a natural being in its own universe, it isn’t subject to any physical laws whatsoever, although it may exhibit regularities in its behavior. What it’s made of, or whether it has any internal structure, are questions which theologians rarely consider.

As I said, there’s much debate about whether this is even a logically coherent notion, or whether it’s so poorly defined as to be a self-contradiction. The point is well-taken that gods like this are usually only defined in negative terms. Saying a being is “immaterial” or “ineffable” doesn’t explain what it is, only what it isn’t. Saying it transcends time and space doesn’t explain in what manner it does exist, cogitate, and act. Saying it consists of “pure spirit” is a meaningless string of words when we have no other examples of this substance to examine. Most attempts to define a type III god, ultimately, consist of mysteries piled upon mysteries, all topped with a generous helping of contradiction and paradox.

So, yes, I can accept the point that the type III god is so ill-defined that we could never be sure whether we’d encountered one, or whether any plausible god-claimant was “only” an example of a type I or II.* But here’s the important thing: as far as we’re concerned, it doesn’t make a difference. We could never threaten or oppose either a type II or III.** If it demanded worship, and your paramount desire was not being blasted into oblivion, you’d have no choice but to obey. Conversely, if you refused on principle to worship any being that hadn’t proved itself morally worthy, it wouldn’t matter what the source of its power was.

From a practical perspective, then, the type I, II and III beings would all be gods to us. If such a being manifested before us and directly communicated with us, logically our response should be the same in all cases. Of course, that would only be a concern for a plausible manifestation. The vague, subjective internal promptings claimed by most religions could never qualify, nor could the many-times-retold tall tales in scripture. It would need to be something clear, direct, and unmistakable, and if experience is any guide, that’s a standard that no religion is likely ever to meet.

* There are differences between the various types. There are certain feats that a type II or III god could perform that a type I couldn’t, for example changing a law of physics. But a type I god could probably craft an illusion realistic enough that we’d never be able to see through it.

** In theory, we could become powerful enough to overthrow a type I, but it’s also possible that it would keep a sufficiently close watch on us to make this a practical impossibility. Arthur C. Clarke’s Childhood’s End is an example of this.