Abstract

Analysis of Competing Hypotheses (ACH) promises a relatively objective and tractable methodology for ranking the plausibility of competing hypotheses. Unlike Bayesianism, it is computationally modest. Unlike explanationism, it appeals to minimally subjective judgments about relations between hypotheses and evidence. Yet the canonical procedures for ACH allow a certain kind of instability in applications of the methodology, by virtue of supporting competing rankings despite common evidential bases and diagnosticity assessments. This instability should motivate advocates of ACH to focus their efforts toward creating structured methods for individuating items of evidence.