22. Filtration Structures and the Cut Down Problem for Abduction
Dov M. Gabbay, John Woods · University of Toronto Press eBooks · 2005
It is widely supposed that when an abductive reasoner seeks for an hypothesis that solves his problem that he makes a search of a space of possible candidates, which he successively cuts down to a space of relevant possibilities, thence to a space of plausible conjectures, and then if he is lucky, to a unit set of these. It can be shown that for any abductively correct determination of such an hypothesis that there is a propositional organization, called a filtration structure, in which that hypothesis has a determinate place. In this paper we examine — and reject— the suggestion that abductive reasoners achieve their ends by solving the Cut Down Problem, and that they do this, in turn, by constructing the requisite filtration-