William Lane Craig sketches out another reason for God’s existence called the Fine Tuning Argument. It utilizes all those wonderful laws and constants of the universe and points out that if their values had been an inch or so different there would be no life; so therefore the universe would appear to be fine-tuned for life. It goes as follows:
1) The fine-tuning of the universe is due to either physical necessity, chance, or design.
2) It is not due to physical necessity or chance.
3) Therefore, it is due to design. (Craig 161)
It is fairly obvious that the soundness of this argument relies on the 2nd premise. It is similar to Moreland’s design argument based on possibility probability, only a little bit more expansive and refined. Craig first casts out the two options of physical necessity and chance and then settles on design.
Physical Necessity (the values and constants must be the value that they are): Craig explains that this seems rather plausible and I rather agree with him. It does not seem like there are any reasons to except this, though the multiverse hypothesis may provide something like this. However I can’t really see any good reasons to believe that multiverses exist either, though if some good evidence or reasons could be given in order to show that they do it may solve the problem. Actually their existence may be more than or at least equally as plausible as a God’s—perhaps I will pursue that further later.
Chance: To show that chance is an implausible hypothesis Craig uses an illustration from John Barrow:
Take a sheet of paper and place upon it a red dot. That dot represents our universe. Now alter slightly one or more of the finely tuned constants and physical quantities… As a result we have description of another universe, which we may represent as a new dot in the proximity of the first. If that new set of constants and quantities describes a life-permitting universe, make it a red dot; if it describes a universe which is life-prohibiting, make it a blue dot. Now repeat the procedure arbitrarily many times until the sheet is filled with dots. What one winds up with is a sea of blue with only a few pin-points of red. (Craig 164)
One objection to this is similar to the objection to the possible design argument laid out by Moreland; and that is that there is no reason to assume that possible reasons are equally probable and that we do not know the values that any given constant can take. In response to this Craig asserts that “in the absence of any physical reason to think that the values are constrained, we are justified in assuming a principle of indifference.” (pg 164) But this gives us infinitely many universes; if each value is equipossible we are left with infinitely many possible values. This will be a very large sheet. It seems like this would be a nice stopping point for Le Poidevin’s criticisms. What Le Poidevin says is very simple: the notion of chance is being applied to a concept in which we cannot possible apply it. This is related to the criticism above. Because the beginning of the universe was such an oddity in time it would not really make sense to say that any constant had a probability of obtaining. For example if one flips a coin we have a ½ chance that the coin will land heads, but if one flips a universe how could we possible tell what the chances are of it being life-permitting. Just like Craig one could conclude something along these lines and arrive at the opposite conclusion: in the absence of any physical reason to think that the values could be otherwise, I am justified in assuming that the fine-tuning is due to physical necessity. In response the defender of this argument may point out amongst other things that is very conceivable that the antimatter could be proportioned differently to the primordial matter or that the big bang could have expanded at a faster rate then it did. But at the same time it is very plausible that the antimatter and primordial matter had a very very constrained value pool to choose from and that there is really no surprise that they achieved the proportion that they did. Again in response the defender could reply that there are many instances of Fine-Tuning and that still leaves the expansion rate of the big bang unexplained as well as the values of gravitation force ect, and could ask what are the chances of all of these things having a constrained value set to choose from? And in response the atheist appears to be justified in saying who knows! It would seem as though we don’t have the ability to explain the fine-tuning of the universe.
Craig, William L. Reasonable Faith: Christian Truth and Apologetics. 3rd ed. Vol. 1. Wheaton, IL: Crossway Books, 2088. N. pag. 1 vols. Print.
Le Poidevin, Robin. Arguing for Atheism: An Introduction to the Philosophy of Religion. London: Routledge, 1996. N. pag. Print.