The Fine Tuning of the Universe
The fine tuning argument is meant to lend inductive support to the existence of God – it is not a standalone argument but rather one to be included in the theist’s toolbox. The argument itself is very straightforward, so I’ll look at the most common complaints and address them as well.
Our contemporary physics tells us that miniscule changes to constants of our universe, such as the energy density of the vacuum, would render life impossible. Not in the sense that our form of life would be impossible (maybe some exotic sort of life could persist?) but in the sense that the universe would collapse before stars could form, expand so quickly that particles could never meaningfully interact, etc. The concern isn’t that our type of life would not exist but rather that nothing we could possibly call life, hell, even the universe itself, would exist. It’s not particularly important that these values are so delicate – it says nothing about their likelihood. Perhaps the only sort of universe would be our own. The tricky part comes upon the fact that there is an enormous range that these values could have been, and this is certainly the sort of contingent fact that begs for an explanation. 😉
The theist will claim that this sort of fine tuning is evidence for the existence of an intelligent designer who, obviously, finds life to be a good thing (this is inference to the best explanation). It should be clear now why the nature of this argument lends it unpersuasive as a standalone, but coupled with something like a cosmological argument it becomes a more reasonable proposition. So what are the common complaints? I’m going to address the two big ones.
Does it make sense to ask why certain seemingly improbable conditions obtained when those conditions obtaining is necessary for one to even be asking the question? The anthropic principle.
There’s a great analogy for this sort of concern, though I do not remember who it’s properly attributed to. The idea is that this sort of question is along the lines of a puddle marveling at how the hole it finds itself in is perfectly formed for its existence – we know that it’s entirely unsurprising that a puddle would find itself in such a situation. There’s no great mystery, the puddle was just designed for the hole. I think I ruined the clarity here, but whatever. I’m going to assume that the general concept is clear. So we can phrase this complaint as it being meaningless to wonder at the fine tuning of these constants, no matter how unlikely, because we could never be asking the question anywhere else!
The start of this response is to point out where this principle works, and why it does. It is very successful with life on Earth – even if life is a rare happening in the universe, there is such an enormous number of trials (planets/moons) that it was inevitable that life would show up somewhere. And from the perspective of that life things would seem designed just for them, even though the existence of that life was mundane and guaranteed. But this works because there are an enormous number of trials – yet there is only one universe. If life starting on a planet is one in a billion it is unsurprising when there are trillions of planets; however, if there were only one planet, it would be quite remarkable. In order to carry on this complaint a person has to posit an infinite multiverse landscape where each constant is randomly placed along its range. In such a situation there is bound to be a universe like our own. The existence of multiverses, especially this type of multiverse landscape, is merely theoretical – it lacks the force of the planetary response.
In addition to this we can illustrate that this response is at least often untrue with a thought experiment. Imagine that the devil takes a strong dislike towards you and wants to kill you, but, out of some twisted sense of “fairness,” will roll a standard die one million times – if he, on any attempt, rolls a number other than 1 you will be killed. He rolls the die a million times and it lands on a 1 each time. Here we have a situation where him rolling a 1 is completely improbable (and that’s a ridiculous understatement), you can only marvel at the improbability by being alive, and yet it is painfully obvious that explanation can be asked for. Doesn’t it seem much more probable that the die was somehow weighted rather than your being incredibly lucky?
You have no idea whether this universe is unlikely or not. With the die you know the odds, but we only have the experience of this universe – we are simply incapable of making judgements about the prior probabilities.
I think this is a good complaint, but I think a thought experiment can make us less certain of it. Just imagine a universe very much like our own but their scientists discover that on each fundamental particle there is an inscription, and it reads “Slurk was here!” Now those scientists only have experience with that universe, and for all they know every possible universe would have such an inscription on the fundamental particles, but surely we would find it very, very reasonable for them to posit that their universe was a simulation, that the designer of that universe spoke English, and that the designer was named Slurk. Whether or not the fine tuning of our universe is analogous to finding such an inscription is open to debate, but this exercise shows that we can acceptably draw conclusions about likelihood without knowing prior probabilities.
There is also a really poor and confused complaint that comes up in the dens of New Atheism: how could the universe be fine tuned for life when so much of it is violently uninhabitable?
If this were not so common I would not even bother listing it, but since I did, let me point out the problem with this. First of all, it’s not even addressing the theist’s argument; the theist is hardly unaware that people cannot go live in stars, black holes, or empty space. The argument is not that the habitability of the universe is evidence for design, it’s that the universe is one that supports life (coupled with our knowledge about physics). It’s attacking something that nobody is fighting about. The theist cares that the “clockwork” of the universe pops out life considering all of the other possibilities.
As if not understanding the argument were bad enough, these people are apparently oblivious to the fact that these dangerous areas are essential or the result of an essential for life. Stars are required for the creation of heavy elements, and black holes are the result of a star’s life – as one example. Anyways I’m sort of rambling on this one, but it’s a stupid, stupid response.
Is life a good thing?
This is sort of a curious after thought, but it seems that this argument assumes that the designer has a desire to create life – after all, we are inferring a designer from the existence of life coupled with the background conditions. But if we were to come to a conclusion that life is not a good thing – or at least that creating it is not a good thing (maybe anti-natalist positions?) – then it seems like this sort of designer could not be the omnibenevolent God of Western monotheism. I’m not sure if I’m right about this, since I’m just writing stream of consciousness, but maybe that’s another option (though committing to anti-natalism might be a tough bullet to bite).
Anyways, that’s the fine tuning argument. I think it’s not bad when given the appropriate role (meaning, when combined with other arguments).