Barker and Achinstein on Goodman

Abstract

Barker and Achinstein think that it is not possible for a predicate like ‘grue’ to serve as well as a predicate like ‘green’ in the role of a qualitative or non-positional predicate. Their arguments consist in a number of attempts to show that one who possesses ‘green’ in his language can do things with that predicate which one who must work with ‘grue’ instead cannot do. However, they succeed in showing only that a qualitative predicate is better adapted to our needs than its positional counterpart, rather than that ‘grue’ is not capable of being a qualitative predicate.