Piecewise versus total support: How to deal with background information in likelihood arguments

Abstract

The use of the Law of Likelihood (LL) as a general tool for assessing rival hypotheses has been criticized for its ambiguous treatment of background information. The LL endorses radically different answers depending on what information is designated as background versus evidence. I argue that once one distinguishes between two questions about evidentiary support, the ambiguity vanishes. I demonstrate this resolution by applying it to a debate over the status of the 'fine-tuning argument'. © 2014 by the Philosophy of Science Association. All rights reserved.