Tuesday, 18 February 2014

The "Fine Tuned" Argument


The "Fine Tuned universe" argument can be stated thus:

1. The combination of physical constants that we observe in our universe is the only one capable of sustaining life as we know it.

2. Other combinations of physical constants are conceivable.

3. Therefore, some explanation is needed why our actual combination of physical constants exists rather than a different one.

4. The very best explanation of the given fact is that our universe, with the particular combination of physical constants that it has, was created out of nothing by a single being who is omnipotent, omniscient, all-loving, eternal, and interested in sentient organic systems, and that he “fine-tuned” those constants in a way which would lead to the evolution of such systems.

5. But such a being as described in (4) is what people mean by “God.”

6. Hence [from (4) & (5)], there is good evidence that God exists.



This argument is basically a variation on the argument from design. The difference is that it misrepresents scientific evidence to support an unscientific conclusion. A more logical conclusion would be to state that there is some unknown natural explanation to explain this apparent "fine tuning". There are also well known arguments which counter fine tuning, such as the natural-law argument, and the anthropic principle.

The argument fails in premise 4 because it baldly asserts what the "best explanation" is without demonstrating why. There is no evidence that constants are 'fine tuned' at all. The premise assumes that there is a certain range of values that each constant could have. This approach is fallacious for two reasons. We have no way of knowing what range the constants could possibly have and We don't know how many iterations there were before the values were assumed. 

Quantum physics demonstrates that the existence of a multiverse is a possibility - and therefore there could be an infinite number of universes with infinite variations of those physical constants. Given infinite possibilities, the existence of a universe such as our own is a certainty. 

The argument also assumes that our universe is finely tuned for the purpose of supporting life. There is no reason to assume this. When we look at the overall composition of our universe, it appears to be far more suited to the creation of black holes than life. Life on our planet constitutes an insignificant portion of our universe. For some reason, creationists do not argue that Venus has been fine tuned with an atmosphere of 96% carbon dioxide and a temperature of 500 degrees, to prevent life existing there. If so much of the cosmos, and indeed our own planet, is uninhabitable by life, then why should we call the universe "fine-tuned"? Why would an omnipotent creator constrain life to a tiny fraction of the universe? 

Even though life exists on Earth, this planet is hardly "fine tuned" for life, and in particular most of Earth is intensely hostile to human life. What we observe is that life fine tunes itself for the conditions on Earth, by means of natural selection. 

The fundamental physical constants have to be independent for the "improbability" argument to work. For example, we can't assume that the gravitational constant and the rate of expansion of the universe were individually "tuned" since they are clearly related. Ditto the electromagnetic force and the speed of light and so on. If the physical constants that define our universe were set by God as part of His creation, then God can adjust those parameters to any values he wants. Therefore the claim that life can only arise under a very specific set of circumstances collapses. If such a God exists, life should be able to arise under any set of circumstances, with infinite possibilities. But if God cannot adjust these parameters, God is no longer the creator of those parameters and there is someone more powerful who did create them and who can change them. 

The fine tuning argument suffers the same problems as other "designer" type arguments, because the creator would also have to be fine tuned by something greater than Himself. If a designer is required for life to exist, the universe must have such properties that warrant a designer. However such a designer would exist in an environment where none of these properties were true. Therefore any properties which apparently require a designer can't be necessary for existence in the first place, as the designer can apparently exist without them. The argument is self-refuting.

For the fine tuning argument to make sense, it has to start with an assumption that human life is not an accident, which begs the question of a creator. But since the purpose of the argument is trying to prove that there is a god who is the creator, then it is a circular argument. 

The case for a supernatural "designer" would be more plausible if humans found themselves living in the vacuum of space, or on Venus, or somewhere where our survival was a mystery to scientists. In fact we find life only where the facts of biology tell us it can exist. This is exactly what we should expect if we were not the products of a cosmic designer. 

The argument assumes that the creator is "a single being who is omnipotent, omniscient, all-loving" but no reason for this assumption is given. It's possible the creator died just after his creation was complete, or that he or she had access to very advanced technology but is not omnipotent. The creation of a universe does not require any of the properties assigned to the creator in premise 4 - so why include them? All physical parameters are irrelevant to an omnipotent God. "He could have created us to live in a hard vacuum if he wanted."

"Why did God issue just those natural laws and no others? If you say that he did it simply from his own good pleasure, and without any reason, you then find that there is something which is not subject to law, and so your train of natural law is interrupted. If you say, as more orthodox theologians do, that in all the laws which God issues he had a reason for giving those laws rather than others -- the reason, of course, being to create the best universe, although you would never think it to look at it -- if there was a reason for the laws which God gave, then God himself was subject to law, and therefore you do not get any advantage by introducing God as an intermediary"
-Bertrand Russel

"The intelligent beings in these regions should therefore not be surprised if they observe that their locality in the universe satisfies the conditions that are necessary for their existence. It is a bit like a rich person living in a wealthy neighborhood not seeing any poverty. What I have done is to show that it is possible for the way the universe began to be determined by the laws of science. In that case, it would not be necessary to appeal to God to decide how the universe began. This doesn't prove that there is no God, only that God is not necessary. One does not have to appeal to God to set the initial conditions for the creation of the universe, but if one does He would have to act through the laws of physics".
-Stephen Hawking

"The features of humanity have evolved as a result of our environment, rather than our environment being tailored to suit us - a flag points north because the wind blows north; the wind doesn't blow north to ALLOW the flag to point north."
- Douglas Adams

Also see this essay by Victor Stenger

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