Alex O'Connor on The fine-tuning argument
O'Connor finds fine-tuning the most intellectually interesting theistic argument but ultimately unpersuasive, favouring naturalistic alternatives.
O'Connor has described the fine-tuning argument as the strongest in the theistic arsenal — a rare concession among popular atheists. He acknowledges that the apparent calibration of physical constants is genuinely striking and not easily dismissed. But he argues that the inference from fine-tuning to a designer commits a subtle error: it assumes that the probability of fine-tuning on theism is high, when in fact we have no way of calculating what a God would or would not create.
He takes the multiverse hypothesis seriously as an alternative, noting that it is not an ad hoc invention to dodge the argument but arises independently from inflationary cosmology and string theory. If a vast ensemble of universes with different constants exists, our observation of life-permitting constants is unsurprising — a straightforward application of the anthropic principle.
O'Connor also presses the point that fine-tuning, even if it establishes a designer, does nothing to establish the God of any particular religion. The distance between 'the constants were set by an intelligence' and 'that intelligence is the trinitarian God who became incarnate in first-century Palestine' is enormous, and fine-tuning does not bridge it.
“Fine-tuning is the argument I take most seriously. But taking it seriously means being honest about what it can and cannot establish — and it cannot get you to Christianity.”