What is empty space? Philosophers in the tradition stemming from Newton, through say Bertrand Russell down to, say, David Lewis, have thought of empty space as a manifold of things called points, and a region of space as empty if no material thing is located at any of the points in that region. These points possess locations and stand in spatial relations to one another; that is, they are things that possess properties and relations (rather than being properties or relations in themselves). There is a rival tradition (stemming from Leibniz) that dispenses with any such things as ‘points of space’ and countenances only material things and properties or relations among them. We will discuss a third option: a property theory of space. Spaces in general (including for instance ‘colour space’) are manifolds of properties; and location space is a manifold of locational properties. This way of thinking opens the possibility of a true void, a region consisting of locations that are not occupied by anything at all—not even by ‘points.’
Monday July 6, 2026 11:00am - 11:55am AEST Steele-206
Social metaphysicians have largely neglected to address what happens when a group loses all of its members. While Hanschmann (2023) argues that social groups can never be memberless, I argue that social entities like clubs, bands and sports teams can be temporarily memberless. Epstein (2015) points out that we have good reasons to accept that entities like the U.S. Supreme Court may persist, in some form, when they lose all their members for a short time and regain new members at a later date. I suggest that there are two plausible ways to account for temporary memberlessness: 1. We could say that social groups can persist without members or, 2. We could say that something persists through a period of memberlessness, but that it is not a social group. The second option may be attractive to those who endorse the social integrate model of social groups, which distinguishes between social groups as member-having entities and institutions more broadly. I argue that the best approach is to treat the property of 'being a social group' as a temporary property that institutions can have.
Monday July 6, 2026 12:00pm - 12:55pm AEST Steele-206
Recently, a group of philosophers, often dubbed 'impossible-worldists' have embraced impossible-worldism—a view that accepts impossible worlds into their ontological category. According to impossible-worldists, by accepting impossible worlds, many hyperintensional phenomena which possible world frameworks cannot address can be accounted for. For example, it is claimed that impossible worlds can account for the hyperintensional phenomena of propositions, doxastic states, counterpossibles, and truth in impossible fiction. However, this paper presents an argument against impossible-worldism. I will argue that there is a dilemma for impossible-worldism; impossible-worldists will either beg the question on determining which kinds of impossible worlds they accept or will neglect specific cases of problems they claim to account for. Specifically, the impossible world framework inherits the same problem from the possible world framework when it deals with impossible objects which are not constituted by possible objects, when these impossible objects are referred to by proper names.
Monday July 6, 2026 2:00pm - 2:55pm AEST Steele-206
I begin by asking what naturalising the philosophy of time should look like. I develop an account of it, drawing on work by Steven French and Alvin Goldman, whereby the philosophy of time needs to be continuous with scientific findings about the nature of time and about the human cognitive apparatus. I develop an argument against relying on intuitions in the philosophy of time, as these can be better explained by appealing to psychology and cognitive science than by taking them to be veridical. Finally, I introduce the predictive processing framework, according to which the content of our perceptual experiences is a function of both how the world is independently of us, and of a contribution made by the perceiver herself. I use this framework to argue that temporal intuitions about passage and presentness are better explained as the result of features of our internal model of the world, generated by the predictive processing framework, rather than features of the world itself.
Monday July 6, 2026 3:00pm - 3:55pm AEST Steele-206
Baruch Spinoza is profound and insightful. He conceives the world from a geometrical standpoint, and his geometric method is demonstrative in imitation of Euclidean geometry. He believes that the same principles that govern the universe also govern the nature of things. In the universe, the conclusions of geometry necessarily follow their axioms. In the same way, the ethical and physical things follow from the nature of things. To this effect, he introduces some definitions from which he deduces a systematic structure whose parts are logically connected. Thus, he developed his theory by deductive reasoning.
His entire theory can be summed up in substance, attributes and modes. These are three parts of the universe and the fundamental structures of his entire thought. Substance is the framework of all reality. Attributes are the primary expressions of the substance, either in a bodily form or a conceptual form. The modes are the particular modifications of the substance.
This paper discusses the five interconnecting features in Spinoza's immanent ontology: substance monism, univocity of attributes, the status of modes, immanent causality and relational ethics. It argues that these interconnecting features comprehensively formulate Spinoza’s concept of substance.
Monday July 6, 2026 9:30pm - 10:25pm AEST ONLINE ONLY
