The Fine-Tuning Argument

TL;DR

The paper argues that the apparent fine-tuning of the universe for life does not support design or multiverse hypotheses, but instead suggests that life is adapted to the universe, challenging common explanations.

Contribution

It provides a critical analysis of fine-tuning arguments, showing their limitations and proposing that fine-tuning is better explained by biological adaptation rather than cosmological design or multiverse theories.

Findings

Fine-tuning does not support design or multiverse hypotheses.

Bayesian analysis shows both explanations fail at an explanatory level.

Life is fine-tuned to the universe, not vice versa.

Abstract

Our laws of nature and our cosmos appear to be delicately fine-tuned for life to emerge, in a way that seems hard to attribute to chance. In view of this, some have taken the opportunity to revive the scholastic Argument from Design, whereas others have felt the need to explain this apparent fine-tuning of the clockwork of the Universe by proposing the existence of a `Multiverse'. We analyze this issue from a sober perspective. Having reviewed the literature and having added several observations of our own, we conclude that cosmic fine-tuning supports neither Design nor a Multiverse, since both of these fail at an explanatory level as well as in a more quantitative context of Bayesian confirmation theory (although there might be other reasons to believe in these ideas, to be found in religion and in inflation and/or string theory, respectively). In fact, fine-tuning and Design even seem to be at odds with each other, whereas the inference from fine-tuning to a Multiverse only works if the latter is underwritten by an additional metaphysical hypothesis we consider unwarranted. Instead, we suggest that fine-tuning requires no special explanation at all, since it is not the Universe that is fine-tuned for life, but life that has been fine-tuned to the Universe.