Most of you surely know the fine-tuning argument for God: the claim that the physical constants of the Universe are such as to permit the evolution and existence of life (especially H. sapiens), and the concatention of so many salubrious constants is improbable—too coincidental to reflect anything but a Great Designer. (Its proponents claim that any alteration in these constants would make life impossible.)
This hourlong video interviews proponents and opponents of this argument for God (mostly opponents). They include philosophers, physicists, and believers. Here’s a list. Anybody whose name you recognize in the list below, save perhaps (Lennox and Craig) isn’t convinced by the argument.
Sir Roger Penrose
William Lane Craig
Nearly all the people interviewed reject the argument, largely on the grounds that we simply cannot calculate a priori what the probabilities are of the constants of nature being what they are, and there are alternative explanations for life that are purely naturalistic.
Sean Carroll makes the point that even thinking that there is fine-tuning that allows for the existence of life, that presupposes naturalism, because “God does not need the laws of physics to allow certain physical configurations to exist in order for there to be life. God is infinitely powerful; God can do whatever. The only theory under which the physical conditions need to be exactly right to allow for complex chemical reactions and biology and life and so forth, is naturalism.” I’m not quite sure about that argument, however; how do we know that God’s creation could occur unless the laws of physics were what they are? Could God really create humans in a universe with different physical constants, constants that He determines?
I do recommend watching the video; it gives you plenty of ammunition against those who wield the argument, but examines the argument from various sides, including what theological assumptions go into it. (The problem of evil is offered as a defeater for a God who would create a universe containing humans.) The arguments go further into string theory, multiverses, the cosmological constant, Boltzmann brains, and Lee Smolin’s “cosmological selection” argument for fine-tuning.
In the end, you will likely reject the fine-tuning argument (even the moderator says that there’s no justification for accepting God from this argument), but you’ll also be impressed about how much we still don’t understand about cosmology.