Abstract

In Lowe (2007), I queried the validity of the following inference-schema: This issue is an important one, because it seems to be something like this schema that is relied upon by those philosophers who seek to establish a posteriori truths about the essences of particular entities – notably, particular chemical substances, such as water and gold – by appeal to a combination of empirical information about those entities and certain (alleged) essential truths of a general and a priori character. As one illustration of schema (I), I cited the following inference: I raised various doubts about the validity of this particular inference, whose conclusion (3a) is, if true, an a posteriori truth about the essence of a particular man, John. (Clearly, if the truth of (3a) can be established only by inference from (1a) and (2a), then, since (2a) is undoubtedly an a posteriori claim, (3a) can only be an a posteriori truth.) I also raised more general doubts about schema (I).