Fine tuning argument

September 26, 2009

PostScript: This has turned into a massive post, I do apologize. It’s also kind of dry and not particularly funny. Maybe I’ll see if I can liven it up with pictures or something to make it less daunting.

I believe I wrote a piece on this topic a while ago after some goon gave a talk at an Edinburgh Creation Group meeting but this will be a more structured approach rather than a rant, I hope. The fine tuning argument is something that I’ve seen come up a few times in online discussions and it’s pretty stupid. Not quite up there with the ontological argument which I may write up about soon, but pretty stupid when you come to think about it.

The fine tuning argument simply states that there are a number of cosmological constraints which must be within a certain threshold in order for life to exist, and since they are within those thresholds that allow life to exist, it’s reasonable to conclude that the universe was designed that way with life as it’s purpose. It often comes side by side with arguments about the earth being perfect for human life which I’ll also mention here very briefly, and the strong anthropic principle which is quite similar, but also goes further to say that a universe must have the properties necessary for life, otherwise it wouldn’t exist.

So lets start with the whole Earth being designed for us thing. The argument usually goes along the lines that if the Earth was any further away from the sun it’d be too cold for life, and any further away, it’d be too cold. If the moon was any closer then the tides would cause massive flooding which would make land based life impossible, any further away and the tides wouldn’t be enough which means a lot of water based life forms wouldn’t be able to survive, things like that.

Well I have two arguments agains this. First of all is that life has evolved on this planet to adapt to its environment. Yes we couldn’t survive if it was too cold, but if it was a little more cold other life forms could have arisen. We do have some beings on this planet living in very difficult conditions. Similarly if the tides were different, we would have evolved differently, just as if gravity was greater on this planet we’d have evolved a lot differently. The second argument is that we shouldn’t be surprised that we are able to live on this planet, since this is where we live and those conditions are necessary in order for the development of an intelligent observer. If this planet wasn’t capable of supporting life, then we wouldn’t be here, just as if another planet that now isn’t capable of supporting life was, then life may have evolved there and they’d be saying the exact same thing. It’s no coincidence that life has developed in conditions suitable for life. As Douglas Adams was known to say, a puddle wakes up one morning and thinks: ‘This is a very interesting world I find myself in. It fits me very neatly. In fact it fits me so neatly… I mean really precise isn’t it?… It must have been made to have me in it.'” This is the weak anthropic principle. If there are more planets capable of supporting life than the inverse probability of life developing on any one of them, then actually life developing somewhere in the universe would be a statistical certainty rather than something to be surprised about.

Then we get to the fine tuning argument itself which is that not only is the planet designed to support us, but the universe too. So if the strong nuclear force was a bit different then heavier elements would be impossible to make, meaning life wouldn’t have formed, and if the Big Bang had expanded any slower it would have collapsed leaving not enough time for life to develop.

There are a great many arguments against this. First of all, to notice that the VAST majority of the universe does not support life, and then to claim that the purpose of the universe is to support life, is massively arrogant. Clearly the universe is better suited to making black holes than it is to supporting life, since we have observed many black holes and are yet to observe a planet with life other than ours (ok, black holes are also easier to observe but you get my point). The supporters of this argument are arbitrarily deciding that life is the purpose of the galaxy, even though it does other things much better. There is no reason to suppose that any natural phenomenon requires a fine tuner any more than any other, other than subjective judgement. In fact human beings have created areas far more finely tuned to supporting life than even just the planet Earth, never mind the rest of the universe. If we can do better than this creator, well then I’ve got better things to do than waste my time worshipping this lousy intern with a bad attitude.

Secondly, many of the constants are related so although Hugh Ross says he has 101, it’s actually much fewer than that. For example the force of gravity and the rate of expansion of the universe are related, and cannot be changed independently. This reduces the odds considerably.

Thirdly, we can also apply the weak anthropic principle to this argument. It’s entirely plausible that there could be a multiverse out there with a universe for each one of the possible combinations of the cosmological constants. Many of them may have ended by now since their particular combination rendered a universe un-maintainable. Many of them may not have even started. In this case, just as it’s no surprise that we’re on a planet that supports life, we should not be surprised that we’re in a universe that is capable of supporting life, since we are, you know, alive.

At this point the religionist will point out that since there is no evidence of a multiverse, then it is faith just the same as believing in a creator. My response to that is that it is a small leap of faith, but nothing like to the extent that belief in a creator is, since we live in one universe and see no reason why something similar could not exist outside of it, whereas we have no experience of anything like a being capable of creating a universe.

On a similar vein, it could also be that the cosmological constants are different in different parts of the universe. We have only observed a very small part of the universe and although I’m not so big on physics that I know it’s possible, it’s not beyond question. If we live in an oscillating universe, every time there’s a big crunch it could be that the cosmological constraints are scrambled. The idea of a fine-tuner is one that I don’t really accept because it implies that there’s some kind of machine with knobs that are turned by someone, which assumes the conclusion and begs the question, but let’s say that the universal constants can be changed and are, at random. Maybe in the vast majority of cases a universe isn’t possible, so the constants keep scrambling until a Big Bang happens. Maybe only a fraction of those universes are capable of supporting life, but again with the weak anthropic principle we should not be surprised that we live in one that does.

Just as a bit of an addition to this point, it could be that the constraints of our universe are conducive to the development of many different forms of life. This would kind of piss on the fire of a religionist who considers humanity to be the sole point of the universe. It could also be that a fairly wide range of universal constants different to the ones we enjoy in this universe may be conducive to the development of some kind of life. This reduces the magical properties of the universal constants we have and reduces the odds of life developing considerably.

Additionally, we don’t know how the universe works and we have no idea how many different combinations of the universal constants are possible! Without such knowledge, claiming that the constants have been fine-tuned is nothing more than speculation.

Now I’m going to get a little more philosophical and try to argue that the argument is actually self-refuting, partly inspired by the “Why God almost certainly does not exist” chapter of Dawkin’s God Delusion (which in that context I actually don’t think is a particularly good argument, but whatever). The argument claims that in order for life to exist there must have been a creator who fine tuned the constants. And yet in the same breath it assumes the existence of a creator who existed in conditions that did not require a creator. So either the initial premise that these conditions require a creator are false, or we have an infinite regress of creators fine-tuning the universe to make the existence of the next creator possible.

Additionally, it could be that the probability of the constants being the way they are is lower than the probability of the existence of a supernatural creator. That would make our existence unlikely, but a naturalistic explanation more likely than that of a creator, which means it was just a lucky roll of the dice.

The final part of this set of arguments (and I promise this’ll be short) is that the universe must contain life, else it would not exist. Well, that’s just a lie. The universe would still exist if there was no life in it, it would just go unobserved.

So I think I’ve made a pretty strong case. Sorry about that.


The Nature of Faith

October 20, 2008

I know I’ve already done a few pieces on the issue of faith, but it’s come up a few times recently at the ECG and at Student Alpha, and I want to address a couple of specific claims.

Firstly, at Alpha they were saying that we use faith for everything. Sitting on a chair, for example, you don’t know if it’s going to support your weight but you put your faith in it. I later said in the discussion that it’s a totally different kind of faith. From experience you know that most chairs do support your weight because that’s what they’re designed to do. So even though it’s not 100% certain that it won’t collapse, you can be fairly sure. Someone gave the other example that you put faith in all kinds of experts who say things about which we have little to no idea, such as your doctor’s medical advice, but again this isn’t blind faith. Scientists and even just academics in general go through a lot in the way of peer review to get their work published, as I’m sure Tim over at the Friendly Humanist will testify. The faith that you put in these kinds of everyday things is also not unfounded, it is again based on experience. You can’t really say the same about religious faith. So just because we sometimes use the same word to describe it, doesn’t make it the same thing.

It was said at the ECG that you must put faith in any account of the origin of the universe and that God is one of those accounts. Particular attention was drawn to people believing in the multiverse theory in spite of the lack of evidence, and that this is no different to faith in God. I have a couple of points to make about this.

1. Belief in the multiverse theory is not totally unfounded, it is to a small degree based on experience. We live in one universe, why could there not be other ones like it? Similarly there’s no reason to suggest the Universe could have existed forever, why does it have to be a beginning?

2. As I’ve said about a gazillion times, I have no problem with the deist idea of God as the first cause, or the idea of Spinaza’s God; it’s just as valid as any other origins theory. But this is totally different to the personal Christian God that the people at the ECG were talking about. It is not a case of accepting all or nothing.

There’s also the issue that I don’t put faith in things that are really important. I wouldn’t advocate the use of faith in something so important as whether to worship God every day of my life or not, or what to believe on certain contentious moral issues that have an effect on everyone. That I leave to reason, as I think we all should.