Heuristics within Heuristics
Timothy L. Williamson · Oxford University Press eBooks · 2020
Since the suppositional heuristic is quite abstract, in practice further applications of heuristics may be needed to implement it. One strategy is to partition the relevant space of possibilities into separate, comparatively homogeneous cells, apply the suppositional heuristic to each, and combine the results. The effect is typically to equate the probability of the conditional with the conditional probability locally but not globally; however, the outcome is then sensitive to which partition is used. This chapter discusses such a strategy, and also the problems raised by conditionals embedded in the antecedents or consequents of conditionals, which lead to applications of the suppositional heuristic to simpler sentences as a subroutine within its application to the complex sentence.