Abstract

Attempts in the 1970s to outline Ockham’s modalities are helpful as they point out the temporal character of Ockham’s theory of modalities. However, this important insight has been neglected for several decades. Falessi and Schang's work (2023) is one of the few recent serious attempts to work out a semantic for Ockham’s modalities, but it resorts to possible worlds semantics and largely disregards temporal aspects. This paper begins with a synopsis of important modern approaches to semantics for Ockham’s modalities, and proceeds with a discussion on methodological problems concerning a representation of medieval logic and a clarification of Ockham’s modal terms. After that, it examines Falessi and Schang’s approach in detail, and assesses it against Ockham’s own texts and understandings. In doing so, we identify what is inadequate in Falessi and Schang’s reconstruction, enabling a return to Ockham’s own texts and with the aid of modern logical tools the development of a new approach to represent Ockham’s understanding of modalities. We ultimately arrive at a time-based relational semantics without branching time for the representation of several key features of Ockam's modalities