How do we know the universe is finely tuned for human life?

I recently received a question about the Fine Tuning Argument.  The question was why should we think that the universe was fine-tuned for life just because it fits our form of life?  Why not think that, had the laws been different, a different form of life would have evolved?

My response is below:

You’ve raised a great question!  Surely ours is not the only form of life that could have existed, so why couldn’t one of those other forms of life come about?

I think we may be underestimating the drastic consequences if the constants and quantities strayed from their current ranges.  What we find is that life of any kind would be impossible.  If the cosmological constant varied slightly then the universe may have expanded too fast for stars and planets to form.  If the gravitational constant were slightly stronger, then the universe may have collapsed back into a singularity shortly after the big bang.  If the nuclear forces that hold atoms together varied slightly then atoms themselves may not have formed, and chemistry would be impossible.

When you see the fine-tuning, argument described we are talking about how finely tuned the constants and quantities are so that life can exist at all.  The problem is far greater than life of our kind being impossible, but rather life of any kind would be impossible.

On Guard by Dr. Craig is a great book for this and other arguments.  In that book he details the arguments and he reviews various objections and shows where they fall short.  I strongly recommend that book to you and your son!


Matt Bilyeu

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