But who caused the Big Bang?

March 31, 2010

The supernaturalist believes that a supernatural god created our universe. Why would the universe need something to create it?

The question itself is neither irrational nor irresponsible. Science is based on curiosity, and the drive to explain origins. Cosmologists are busily trying to explain how a universe could start from a hot explosion of energy, and trying to explain where that energy could come from.

Rationality itself is behind good explanation. Expressed simplistically, scientific reasoning prefers rules such as "an event must have a prior cause" and "the origin of a thing is due to something else" and "something that didn’t have to exist must be the responsibility of something else." These are various ways of saying that something can't come from absolutely nothing. Science is intelligently designed to find the connections between things.

The universe appears to be an event, with an origin in the Big Bang. There has been much talk about the universe "coming from nothing" but we should be more precise with our words. Since it turns out that any quantum vacuum nothingness is actually a seething chaos of potential somethingnesses, cosmology won't be saying that the big bang came from absolutely nothing. But who could say what the cosmological story about the big bang will look like a generation from now, or a hundred years from now? I doubt cosmology will settle for "well, it did come from absolutely nothing." Instead, cosmology offers theories about prior conditions -- like an "eternal inflation" of quantum flux -- that suggest how universes can form and evolve. Our universe doesn't violate the ultimate rule that energy can't come for free -- that is why our universe may have a total net energy of zero. However, saying that our universe adds up to a nothing is quite different from saying that our universe just suddenly came from nothing. Quite the opposite.

Unimpressed by cosmology's perpetual efforts to describe prior conditions before big bang explosions, religion offers its god hypothesis. Hypothesizing a god beyond our universe is one thing, but proving that the only possible explanation is a god must be quite another thing. Naturalists can avoid having to admit that the god hypothesis must be right because it is the only available hypothesis. What could naturalism offer to hold off god?

There is one sort of entity that gets around the positive rules of explanation: anything that is not an event, has no origin, and had to exist is a thing can obtain an explanatory exemption, in principle. Theologians know this interesting principle very well: they often claim that their god meets these criteria, perfectly, so the universe needs explaining, while god does not. That halts the "who made god?" line of questioning. Of course, a god may not be the only thing that could meet these criteria for exemption. What if it is just endless eternal nature that sets the prior conditions for universes? The quantum vacuum is still nature; weird, but natural. Or our universe may have exploded off from earlier universes. It could be "supernature" all the way down, and eternally back in time. You can't assume that a supernatural god is the only candidate for ultimately explaining origins.

To prove that a god caused the big bang, the supernaturalist must first rule out supernature. How could the supernaturalist disprove the supernature hypothesis? We hear theologians say, "Obviously natural things can't be everlasting." True enough, the natural things we see around are busily coming into existence, falling apart, and getting transformed into other things. However, "supernature" might be different. Although individual things within exist in time, have origins, and are not self-sufficient, nature as a whole may not have the same properties. Wholes can have properties that none of their parts possess, so an inference that the whole of nature must be as contingent or dependent commits a logical fallacy.

Supernaturalists try to argue that nothing real can exist for an infinite amount of time, by claiming that it is impossible to conceive how an infinite amount of time has passed before the present time. However, the very definition of infinity requires that conceiving its completion is impossible (if conceiving such a completion were possible, it wouldn’t be a genuine infinity), so this argument misuses the concept of infinity. Either way, supernature may be all that there is, because it may be either ultimately timeless or eternal, and hence entirely self-sufficient. Once again we see how the supernaturalist cannot disprove the possibility that there is only more nature to be explored. Naturally, the supernaturalist prefers that god enjoy the properties of timelessness or eternality, but there is no need for a god hypothesis if supernature could have those properties.

After all this reasoning, we reach a skeptical standoff. No proof for a god lies behind the big bang. But no one is trying to prove the "supernature" hypothesis, either. Science isn't proving that hypothesis; we are operating on a philosophical level here. Naturalists cannot argue that "supernature" is the right answer, therefore no god exists. That's precisely the skeptical standoff, which cannot be avoided. If we must all confess our ignorance of what really was going on before the big bang, then let's stay agnostic and skeptical towards all hypotheses as we await more evidence. That is why our evidence about the big bang cannot justify a god.