Abstract

Three philosophical questions that are often confused should instead be keep distinct: First, what is a thought? Second, what is that in virtue of which a thought is a thought? Third, what is it that determines of what a thought is a thought? These questions raise very different issues within Ockham’s philosophy. Although Ockham’s views about the first question evolve, he seems to answer the second and the third questions in the same way, maintaining throughout his career that the intentionality of thoughts, which he expresses in terms of signification, is a primitive feature of them. Ockham’s view contrasts sharply with the view that can be found in Aquinas and others that a thought is a form of being present in an immaterial way. This alternative view explains intentionality by reducing it to the co-presence of a number of non-cognitive factors. This latter view offers hope of unifying epistemology and such sciences as optics but at the price of a very peculiar ontology. Ockham avoids this peculiarity, but his way of doing so raises issues about what determines the taxonomy of thoughts, and about whether the items which are thoughts are essentially so or whether by God’s power they could exist without being thoughts. Despite Ockham’s terminology of similitude, the taxonomy of thoughts is not fixed by internal features of the metaphysical items which are thoughts but by the objects of the thoughts, and this suggests a negative answer to the questions whether thoughts are essentially thoughts, an answer that Ockham seems not to draw explicitly but which is explicit in the work of some, like Pierre d’Ailly, who are much influenced by him