16 Reasons Why I Believe In God: (4) The Fine-Tuning of the Universe

12:48 PM James 2 Comments

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  1. James,

    Am really enjoying your articles and am looking forward to the ones you've yet to write.

    I wanted to mention another objection I've heard in response to your argument above and get your thoughts. It has to do with the idea that carbon based life is the only form of life possible. Scientists such as Paul Davies, Carl Sagan and others, in the realm of both science and science fiction (such as the talented writers of Star Trek) have written about the possibility that other forms of life may be possible. Someone (Sagan among others) even came up with a rather clever term "Carbon chauvinism" to describe the belief that all life must be carbon based.

    What is your response to the notion that non-carbon based life might be possible, and that the variables we see in nature which you reference above, are suitable for carbon based life, but that if they were different, another form of life (e.g. silicon or arsenic based) might have formed?

  2. Hi Mitch, great to hear from you! Excellent question. I don't think the possibility of non-carbon based life affects the fine-tuning argument at all, for a couple of reasons:

    First, a number of the finely tuned conditions don't just make carbon based life possible, they make *any* kind of life possible. I'll give you a couple of examples: (1) If the range of the strong nuclear force were further reaching (like that of gravity or the electromagnetic force), it would likely pull all the protons and neutrons in the universe together, since it is so powerful. In that case, the universe would consist of a giant black hole, and no kind of life would be possible, carbon or otherwise. (2) If the cosmological constant were larger or smaller than it is, then the universe would either have expanded or collapsed too quickly for stars or galaxies to develop. In either case, no form of life could exist. So, even if it were possible to have silicon or arsenic based life, the fine-tuning of the universe is still necessary for that life to exist.

    Second, just because non-carbon based life is *possible* doesn't mean it's likely. Scientists' belief that all life is carbon based isn't founded on the fact that we've never seen life made of anything else. Rather, it's founded on what we know about physics and chemistry. The atomic structure of carbon makes it the best candidate for life. From what we know about the chemical elements, it would possible, but more difficult to make life out of something like silicon or arsenic. And if the universe must be this extremely fine-tuned to support carbon-based life, it could ironically need to be even *more* fine-tuned to support non-carbon life; since that life would not be as flexible or rich as its carbon based counterpart.

    All that to say, it's perfectly possible that life could be made of something other than carbon. But that in no way affects the fine-tuning argument, because non-carbon based life needs fine-tuning to exist just as much as carbon based life does; it might even need it more.