This is the third part of a series discussing the Fine Tuning argument (FTA). The outline is here.

Uncertainty vs Ignorance

Earlier, I showed this plot showing probability distributions for three possible hypotheses of the universe. The FTA contends that the naturalism hypothesis predicts distribution A, and the God hypothesis predicts distribution B.

I will refer to a distinction that is commonly made between “uncertainty” and “ignorance”. “Uncertainty” refers to a situation where you don’t know what’s going to happen, but you at least have probabilities, a way to quantify how much you don’t know. “Ignorance” refers to a situation where you don’t know what’s going to happen, and you don’t even know how much you don’t know. When we compare probability distributions in the FTA, the probability distributions are just cartoons. We don’t have any real probabilities. We’re operating from a state of ignorance, not uncertainty.

Or, in other words, we pulled these probability distributions out of our asses.

The God hypothesis

The FTA is claiming that if God exists, then we have distribution B: the universe will look a very particular way, and that this matches the universe we observe. The idea is that God has intentions, and these intentions are related to the output of the universe, rather than the input. So God doesn’t particularly care how easy or hard it is to fine-tune the universe, all he cares about is that in the end, there’s life.

There are several ways to poke at this argument. For instance, maybe the God hypothesis leads to predictions that are too precise, and not at all matching the universe we observe. For instance, in Christian tradition, God has perfectly moral intentions, predicting not just a world that has life, but also a world that is “good”. Since our world is not all good, this is a very narrow prediction that does not match our observations. So maybe the God hypothesis is more accurately described by distribution C.

Another possibility is that God would prefer a completely different landscape. What I mean is that maybe God would prefer a universe where life doesn’t depend on the parameters of the universe being finely-tuned. It would be a rather friendlier universe, where perhaps humans could inhabit a larger fraction of space rather than having to cling to an insignificant rock in an endless void. Alternatively perhaps God doesn’t really care whether the conditions of the universe are right for life–even if the conditions were wrong for life, God could still create life that miraculously survives anyway.

The point being, that we’re very focused on just a few universal parameters like the fine structure constant, the cosmological constant, the efficiency of hydrogen fusion, but we’re ignoring all the additional parameters that God has at his disposal. Even though God’s goal is to create life, God had many options for how to do that. Our predictions, given the god hypothesis, should be distributed among these many options. We have no idea what that distribution looks like, whether it’s more like A, B, or C.

Or, instead of considering a God hypothesis informed by Christian traditions, let’s consider a more generic god. This god has the ability to create a universe, and has some sort of intentions. But what expectations can we have on the intentions of this hypothetical being that we know nothing about? There are an absurdly large number of things in this universe that have nothing to do with humans, and this god’s intentions could be related to any one of those things instead of us.

The naturalism hypothesis

After explaining how nebulous this God hypothesis is, you might expect me to say that the naturalism hypothesis is rather more mechanical and precise. But this is not the case!

The FTA claims that naturalism leads to the broad probability distribution A. But this isn’t really based on any particular theory. It’s just based on a basic rule of thumb. The rule of thumb is that if we’re given a parameter of the universe, the uncertainty of that parameter under naturalism is roughly equal to the value of the parameter. For example, the fine structure constant is about 1/137, so the uncertainty in the fine structure constant is about 1/137.

But let’s face it, it’s not a very good rule of thumb. And to make things worse, people don’t even apply it very consistently, they mostly choose whatever rule of thumb seems most convenient to the argument at hand.1 It would be better if we had some specific theory that predicts, for example, that the fine structure constant is around 1/110 to 1/150. Or something like that. And we just don’t have a theory like that, at least not one that I know of.

It’s not that it’s impossible to come up with such a theory. I’m sure that some physicists have already come up with theories of that sort, or at least tried. But it’s probably very difficult to come up with a good one, and more difficult still to achieve widespread acceptance among physicists. And even if a theory did achieve widespread acceptance, how many of us would actually understand it? Would any of us, here, talking about the FTA, understand it well enough to incorporate it into our theological arguments? Probably not.

If any current theory is likely to make predictions about the fundamental constants of the universe, it’s probably string theory. So consider the image that string theory has, among the general public. First of all, no one understands it. Not many people particularly trust it. The physicists who study it regularly get accused of living in cloud cuckoo land, doing pure math that has no connection to reality. Whatever you think about string theory, we can all agree that making predictions about the constants of the universe is very difficult. We use the rule of thumb not because the rule of thumb is remotely good, but because our alternative is something like string theory.

Unfairness in tailoring

When it comes to the god hypothesis, I argued that there is a very broad range of predictions, because in principle there are any number of things that God could care about besides life. Typically, we tailor this hypothesis to fit our observations. We see life around us and think, “God must have wanted life”. Somewhere along the way we got the idea that God is all good, but since we see evil around us, we think, “God might be all good but it’s not the kind of goodness that actually excludes evil.”

And perhaps there’s nothing wrong with tailoring your hypothesis to fit observations. I mean, that’s basically scientific reasoning.

But when it comes to the naturalism hypothesis, we also have the option to tailor our hypotheses. The problem is that it’s just too hard.

So from this standpoint, it’s looking a bit unfair. Theists can tailor their hypothesis, because it’s so easy that an ancient civilization has already done it for you. Naturalists can’t tailor their hypothesis, because it’s so hard that we wouldn’t understand it even if a bunch of experts already did the work, and we’d complain that the experts weren’t being scientific enough. In other words, if the god hypothesis is winning, that might be only because it has vastly lower standards.



1. To give an example, earlier I talked about the energy release of hydrogen fusion. It has been claimed that if you changed the energy release by even 0.1%, then that would make life impossible. 0.1% sounds pretty small! However, I think this is misleading. The amount of energy released is 0.7% of the mass of the initial hydrogen atoms, so by my accounting, a change of 0.1% is really more like 1 part in 7, not 1 part in 1000. (return)