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
Presentism is often seen as the simplest most intuitive ontology of time, yet direct comparisons between presentism and eternalism based on simplicity are limited. Philosophical consensus holds that presentism is quantitatively parsimonious but qualitatively identical to eternalism. Presentists also risk introducing qualitative and scientific/structural extravagance in addressing standard objections.
This paper defends presentism on all fronts – quantitative, qualitative, and structural. I, first, examine arguments extolling quantitative parsimony as incidentally virtuous but not inherently virtuous. I propose, instead, a ‘Principle of Sufficient Explanation,’ where inclusion of any explanans must be justified, undermining the traditional quantitative-qualitative asymmetry.
I, then, argue accepting qualitative equivalence between presentism and eternalism concedes the latter’s truth. Instead, presentists should assert that non-present objects are fundamentally different from present ones by undermining space-time analogies and accusing eternalists of inexcuably gerrymandering qualitative categories. Furthermore, I bypass any extravagance introduced by presentist solutions to semantic objections, defending a novel justification of ‘ontological cheating’ grounding truth not in being but in what statements are 'about'.
Finally, I address objections from special relativity, arguing that any structural bloat introduced by presentism in this regard is either subject to uncertain future empirical investigation, justified metaphysically, or simply a descriptive theoretical artefact.
Tuesday July 7, 2026 11:00am - 11:55am AEST Steele-2373 Staff House Rd, St Lucia QLD 4067, Australia
Much of my recent research has centred on the polemic between Henri Bergson and Gaston Bachelard. In particular, I have focused on the notions of continuity and discontinuity within the two philosopher’s work. I have found that recent Bergsonian scholarship has, at times, dismissed Bachelard uncharitably. I ask, however, whether such a hasty dismissal of Bachelard is necessary, let alone justified. My argument is that Bachelard understood Bergson’s work at a depth greater than what he is often credited, and therefore, he provides a critique that warrants a deeper level of engagement from Bergsonians in return. My aim here is not to discredit Bergson so much as it is to develop an interpretation of Bergson that has sincerely engaged with Bachelard’s novel and insightful critique.
Both philosophers present compelling philosophies of temporality that, at the very least, generate an interesting polemic. At most however, I have found that a sincere engagement with the tension found in their opposition has led to a deeper appreciation of both. Personally, I have not concluded my research and my ultimate position on the matter remains indefinite. That being said, I am certain that Bergsonian scholars will benefit from an encounter with Bachelard’s critique.
Tuesday July 7, 2026 12:00pm - 12:55pm AEST Steele-2373 Staff House Rd, St Lucia QLD 4067, Australia
Science makes progress in a way that metaphysics seems not to. From Locke, Hume, and Kant through logical positivists and deconstructionists and down to (for example) David Lewis, Amy Thomasson, Mark Balaguer, John Heil and hundreds of others, philosophers have written engagingly about "progress" in philosophy. Some have concluded that it is time to give up even trying to answer metaphysical questions. I will suggest that Balaguer is right to think that it is prudent to rely on only a very "thin" metaphysics for practical purposes; but also that Heil is right in maintaining that giving up on metaphysics is not an option. I will also try to give a more positive spin to the whole business. There is a reason why answers to metaphysical questions cannot be proved correct; and there are also reasons why this is a good thing, and why this provides a reason for doing metaphysics rather than abandoning it.
Various philosophers have thought that the propensity interpretation of probability faces fatal objections. They include: “Propensities are mysterious.” “We don’t know how propensities behave.” “We do know that they don’t obey the probability calculus.” “Propensities are not Humean supervenient.” And “propensities do not vindicate the Principal Principle” (Lewis’s bridge principle between chances and rational credences).
I will revive the propensity interpretation. In a slogan: chances measure graded dispositions. More carefully, conditional chances measure graded dispositions to produce given outcomes, conditional on specifications of physical situations. Comparative dispositions are entirely familiar. My wine glass is more fragile than my beer mug; salt is more soluble than plastic. And I argue that we can get from comparative dispositions to numerical propensities that obey the probability calculus, answering all of the objections above (and more). Reports of the death of the propensity interpretation have been greatly exaggerated.
Tuesday July 7, 2026 3:00pm - 3:55pm AEST Steele-2373 Staff House Rd, St Lucia QLD 4067, Australia
Debunking arguments aim to show that our beliefs do not track the world, by identifying a certain etiology that confers negative epistemic status to our beliefs. For instance, we believe that murder is wrong. Debunker comes in by stating that we have such a belief because we evolved to belief that murder is wrong given that it is maladaptive. Since that is the case, our moral beliefs do not stand for moral facts. In this paper I aim to put forward a novel type of debunking arguments—the one that pertains to identity. Roughly, I claim that we have intuitions about what makes objects different from other objects and that such intuitions can be debunked. The first intuition—the unity intuition—states that we think that objects are singular if they have enough unity. The second intuition—the spatial boundary intuition—states that we think that objects are singular up to the point where they meet unoccupied space. The claim is that, analogously to a moral case, we evolved to have such intuitions which makes them epistemically problematic. If it weren’t for evolution, we wouldn’t think that objects are singular, nor we would have intuitions about what makes them singular. The upshot is that we have a reason to suspend or reduce credence to our beliefs about identity.
Wednesday July 8, 2026 5:00am - 5:55am AEST ONLINE ONLY
I explore the metaphor of "nothing-over-and-aboveness" and the ontological "free lunch" as it features in neo-Aristotelian and Quinean approaches to ontology. The main question I consider is how should we cash out such talk. Does it track a metaphysically significant relation, or does it simply indicate a lack of ontological commitment? For instance, some metaphysicians, such as Jonathan Schaffer and Karen Bennett, have used grounding relations and explanation to argue that their ontologies are more parsimonious. There appear to be a range of relata and relations that may license such talk. For example, the aforementioned grounding relations, reduction, and identity relations, along with fundamentalia and derivata. I will also consider how the theory virtue of parsimony features in cases from metaphysics as compared to how it features in scientific practice. Finally, I defend the view that there may be no ontologically innocent entities, in line with a Quinean approach to ontology.
Wednesday July 8, 2026 11:00am - 11:55am AEST Steele-262
Was there any event in human history whose occurrence was inevitable? Mainstream theories roughly follow Ben-Menahem’s sensitivity principle, stating that the necessity/contingency of a historical event depends on its degree of sensitivity to the initial conditions of its occurrence. In contrast, I propose to account for historical inevitability using the idea of a (metaphysical) causal sufficient condition. It provides a new theoretical framework and an empirical methodology. The obtainment of a set of events within the target event’s initial conditions, whose types constitute one configuration of the causal sufficient condition(s) of the event type to which the target event belongs, leads to its inevitable occurrence. That is, a historical event token occurred inevitably once a configuration of its causal sufficient condition was realised. Section I briefly illustrates the proposed account. Section II elaborates on explicating historical inevitability by causal sufficient and necessary conditions. Section III draws on interventionist counterfactual analysis to delve deeper into the causal and formal aspects of causal sufficient (and necessary) conditions. Section IV explores an empirical methodology especially suitable for studying the inevitable occurrences in human history. It utilises interventionist ideas to explain the formation of hypotheses of causal sufficient and necessary conditions for applicable historical event types.
Wednesday July 8, 2026 12:00pm - 12:55pm AEST Steele-262
In classical extensional mereology, it is provable that if there are no Fs, then the universe is the general product of the Fs. For example, if there are no unicorns, then the universe is the general product of the unicorns. This paper argues that the source of this counterintuitive theorem lies not in classical extensional mereology itself, but in the classical treatment of restricted existential quantification, according to which if there are no Fs, then all Fs are Gs. For example, if there are no unicorns, then all unicorns have tentacles. It also argues the problem is not resolved by rejecting universalism or extensionalism, nor by adopting free or plural logic.
Wednesday July 8, 2026 3:00pm - 3:55pm AEST Steele-262
In philosophical circles it is widely understood that Michel de Montaigne was a humanist. It is less so understood that he was a Catholic. Drawing on rich experiential research that has culminated in a visit to the cenotaph of Montaigne in Bordeaux, France, the Sanctuary of Our Lady Fátima in Fátima, Portugal, and the Ring of Brodgar in the Orkney Islands, Scotland, Woodman outlines a modern case for the existence of God using a novel humanistic approach.
Wednesday July 8, 2026 4:30pm - 5:25pm AEST Steele-262
Frankfurt-style cases (FSCs) are widely regarded as counterexamples to the Principle of Alternative Possibilities (PAP). In response, Widerker (1995), Ginet (1996), and others have advanced the well-known Dilemma Defense: in any FSC, either the agent is not morally responsible, or the agent could have done otherwise. This defense is often thought to depend on a “prior sign”—an indicator of how the agent is likely to act. To address this, Mele and Robb (1998), Hunt (2000), and others have revised FSCs to eliminate the role of such signs. This paper sets that debate aside and argues instead that all standard FSCs face a deeper structural dilemma, one that arises from the very nature of these cases and does not depend on prior signs. As a result, FSCs cannot serve as genuine counterexamples to PAP.
Thursday July 9, 2026 11:00am - 11:55am AEST Steele-262
Free will skepticism is a position that either doubts or explicitly denies the existence of free will. In contrast, some proponents of free will—particularly compatibilists—affirm its existence by appealing to the concept of "agency." They argue that if individuals act with agency, then, even if determinism is true and their actions lack alternative possibilities or sourcehood, they still possess the freedom necessary for moral responsibility.
However, free will skepticism does not necessarily focus on agency. If a form of free will skepticism can meet the compatibilist criteria for agency while still remaining valid, it would present a significant philosophical challenge. In this presentation, I will examine Galen Strawson’s 'Basic Argument' as an example of free will skepticism and consider the question: "Is free will skepticism incompatible with agency?" I will explore how agency can be satisfied within free will skepticism and whether, despite this, it can still raise fundamental doubts about our freedom and moral responsibility. Such an inquiry, I believe, can help avoid the issue of talking past one another in free will debates, fostering a more productive discussion.
Thursday July 9, 2026 12:00pm - 12:55pm AEST Steele-262
Doomsday is the last moment in time. Nothing comes after. In the recent literature on temporal metaphysics, several theories have been challenged by arguments invoking doomsday. In this talk I focus on the papers of Loss (2019), Andreoletti (2022), and Bigg and Miller (2024). A shared premise in these arguments is that it would be a problem or drawback for a theory of time, if it failed to allow for moments of undetermineddoomsday. In this scenario, time ends, despite it not being determined to by the laws plus the state of the world. Each of these authors argues that this scenario is at least possible, so we should expect a good theory of time to make room for it. In this talk, I argue against this point. In general, if a theory of time is incompatible with undetermined doomsday, then that is merely an interesting but neutral consequence of that theory. More broadly, we can expect various theories of time to be incompatible with various doomsday scenarios, up to and including being incompatible with any doomsday at all. I argue that this is not a prima facie problematic stance to adopt.
Thursday July 9, 2026 2:00pm - 2:55pm AEST Steele-262
This paper explores a possible explanation for why we care about truth. As human beings, we are naturally inclined to seek truth over falsehoods. Normatively, we are also expected to believe and assert truths rather than lies. But why is truth so important to us? One common view holds that truth has instrumental value—it helps us achieve our goals. Another view sees truth as intrinsically valuable, valuable in itself. However, Wrenn (2010, 2017, 2023) argues that both views fall short. He denies that truth itself has value but claims that caring about truth is a moral virtue; we morally ought to seek it. Following Wrenn’s strategy, I will also reject the idea that truth itself has value. Instead, I focus on the process of acquiring truth. I propose that acquiring truth is a kind of achievement, and achievement is intrinsically valuable. The pursuit of truth involves overcoming challenges and exercising our will, a core human character. Thus, the value lies not in truth itself, but in the act of seeking it. By emphasizing the value of achievement, we can explain why we ought to care about truth without assuming that truth is valuable in itself.
Thursday July 9, 2026 3:00pm - 3:55pm AEST Steele-262
