A finely tuned argument

Victor Stenger has a new book, The Fallacy of Fine Tuning: Why the Universe is not Designed for Us. Stenger is a prominent atheist and author of the bestselling book, God: the Failed Hypothesis. [A detailed critique of that book was published in Science and Christian Belief by David Bartholomew, formerly Professor of Statistics at the London School of Economics.]

What is fine tuning? Basically it is the idea that the laws of physics and fundamental constants of nature [e.g. charge and mass of the electron] are "finely tuned" so that carbon based life can exist.  Some argue that this is evidence that we were meant to be and that God designed the universe accordingly. I believe that Stenger claims this argument is flawed because it is "carbon-centric" and that one can imagine alternative scenarios and universes where life is based on a different element (e.g. silicon, which is the basis of computer technology). Alternatively, one might even consider the possibility that life is not based on atoms and molecules but on the dark matter or dark energy which comprises most of the universe.

What do I think about these objections? First, we cannot completely rule out the existence of such alternative "templates" for life. But, these are just speculations and lack specificity. This is similar to the claim/argument that Richard Dawkins makes in The God Delusion that physicists will invent a theory [e.g. the multiverse] that will explain fine tuning, just as Darwin explained the emergence of "apparent design" in biological systems. Alternative new explanations of anything are always possible. But usually in science (and everyday life) we focus on the concrete possible explanations we have access to now and consider their relative merits.

How likely is an alternative chemistry for life? One reason we might be skeptical is that evolution has not produced it yet! Biomolecules do use a diversity of chemical reactions and different metal ions [iron, molybdenum, copper, zinc, manganese, vanadium, ...] are used for different purposes in metalloproteins. But, it seems the template in any and every species is still nucleic acids (for DNA and RNA) and amino acids (for proteins). If one could use silicon to perform some function then one might expect some part of nature to have discovered it. I am reminded of Richard Feynman who said:

'There is no such thing as polywater because if there were, there would also be an animal which didn't need to eat food. It would just drink water and excrete polywater'

Also, for the last 50 years chemists have been desperately trying [with minimal success] to come up with synthetic structures which can perform even the simplest functions [e.g. photosynthesis] that biomolecules do. Stenger is a physicist. But, I think most chemists would acknowledge that there is something very special about carbon based chemistry.

Having said all this, I think caution and caveats are in order. I do not think fine tuning proves that the universe is designed for life. Furthermore, I certainly do not think it proves that God exists. [See Tony Wright's cautionary comments on an earlier post]. To me it is just a fascinating observation which confronts us with questions of a non-scientific nature. Is there some greater meaning and purpose to the universe? The end of science is the beginning of theology.

I thank Stephen Driscoll for asking me some questions that stimulated this post