The fine-tuning argument and the requirement of total evidence

Abstract

According to the Fine-Tuning Argument (FTA), the existence of life in our universe confirms the Multiverse Hypothesis (HM). A standard objection to FTA is that it violates the Requirement of Total Evidence (RTE). I argue that RTE should be rejected in favor of the Predesignation Requirement, according to which, in assessing the outcome of a probabilistic process, we should only use evidence characterizable in a manner available before observing the outcome. This produces the right verdicts in some simple cases in which RTE leads us astray, and, when applied to FTA, it shows that our evidence does confirm HM.