Thomas Aquinas and Some Italian Dominicans (Francis of Prato, Georgius Rovegnatinus and Girolamo Savonarola) on Signification and Supposition

Supposition is a controversial logical theory. Scholars have investigated many points of this doctrine such as its historical origin, its use in theology, the logical function of the theory, or the relationship between supposition and signification. In the article I focus on this latter aspect by discussing how some Italian, and in particular Florentine, Dominican followers of Aquinas—Francis of Prato (d. 1348), Girolamo Savonarola (d. 1498), and Georgius Rovegnatinus (d. after 1500)—explained the relation between the linguistic terms’ properties of signifying and suppositing, and hence the division of supposition. After sketching out Thomas Aquinas, Hervaeus Natalis, and William of Ockham’s positions on the relationship between signification and supposition, I closely examine Francis’s criticism of Ockham. Francis follows Walter Burley’s account of supposition and considers the statement that a term has simple supposition when (i) it is taken not significatively and (ii) stands for an intention of mind as the weak point of Ockham’s explanation of supposition. According to Francis, if this were the case, there would be no semantic basis for differentiating simple from material supposition. Francis is however hesitant about the full subordination of supposition to signification, especially with regards to material supposition, when a term, suppositing for itself, is taken to signify itself besides its meaning. More than one hundred years later, Girolamo Savonarola and Georgius Rovegnatinus have no doubt about the fact that terms may supposit only for what they signify.