Is the Universe Fine-tuned for Us?

The ancient argument from design for the existence of God is based on the common intuition that the universe and life are too complex to have arisen by natural means alone. However, as philosopher David Hume pointed out in the eighteenth century, the fact that we cannot explain some phenomenon naturally does not allow us to conclude that it had to be a miracle. In recent years, novel versions of the argument from design that call upon modern science as their authority have appeared on the scene. Proponents of so-called Intelligent Design claim to confidently rule out natural processes as the sole origin for certain biological systems (Behe 1996, Dembski 1998, 1999, 2002). Here we shall focus on another variation of the argument from design, the argument from fine-tuning, in which evidence for a purposeful creation is seen in the laws and constants of physics. This claim of evidence for divine cosmic plan is based on the observation that earthly life is so sensitive to the values of the fundamental physical constants and properties of its environment that even the tiniest changes to any of these would mean that life, as we see it around us, would not exist. The universe is then said to be exquisitely fine-tuned-delicately balanced for the production of life. As the argument goes, the chance that any initially random set of constants would correspond to the set of values that we find in our universe is very small and