The belief that Aristotle opposes potency (dunamis) to actuality (energeia or entelecheia) has gone untested. This essay defines and distinguishes forms of the Opposition Hypothesis—the Actualization, Privation, and Modal—examining the texts and arguments adduced to support them. Using Aristotle’s own account of opposition, the texts appear instead to show that potency and actuality are compatible, while arguments for their opposition produce intractable problems. Notably, Aristotle’s refutation of the Megarian Identity Hypothesis applies with equal or greater force to the Opposition Hypothesis. (...) For Aristotle, then, potency and actuality are compatible. (shrink)

There are two distinct but interrelated questions concerning Aristotle’s account of infinity that have been the subject of recurring debate. The first of these, what I call here the interpretative question, asks for a charitable and internally coherent interpretation of the limited pieces of text where Aristotle outlines his view of the ‘potential’ (and not ‘actual’) infinite. The second, what I call here the philosophical question, asks whether there is a way to make Aristotle’s notion of the potential infinite coherent (...) and rigorous with modern tools that can stand as a rival to the widely-accepted view of the infinite as characterized in a mathematical theory of sets. In this paper, I argue that the theoretical roles that Aristotle intends his account of the potential infinite to fulfill lead to a deep and irresoluble tension that can help explain the persistence of debates on both of these questions. I do so by turning to the places where Aristotle attempts to argue for or against the existence of particular infinite processes to show that he slides between different underlying notions of when changes are possible. Making these underlying notions clear can help us better understand the role of Aristotle’s account in the history of philosophy, the possible pitfalls for a contemporary theory of the potential infinite, and what each of these debates might learn from each other. (shrink)

A popular claim in recent philosophy of mind and action is that events only exist once they are over. This has been taken to have the consequence that many temporal phenomena cannot be understood ‘from the inside’, as they are unfolding, purely in terms of events. However, as I argue here, the claim that events exist only when over is incoherent. I consider two ways of understanding the claim and the notion of existence it involves: one that ties existence to (...) the logic of quantification, and another that assimilates the existence of an event to that of a continuant. The first of these, I argue, cannot be the right way to understand the target claim, as there are serious logical obstacles to regarding this notion of existence as temporally variable. The second, on the other hand, leaves it ultimately mysterious what the existence of an event could amount to. I close with the suggestion that the undeniable temporal asymmetries which parties to the debate are interested in are properly understood in perspectival, not ontological, terms. (shrink)

In 'Physics' I.7, Aristotle claims that plants and animals are generated from sperma. Since most understood sperma to be an ovum, this claim threatens to undermine the standard view that, for Aristotle, the matter natural beings are generated from persists through their generation. By focusing on Aristotle’s discussion of sperma in the first book of the 'Generation of Animals', I show that, for Aristotle, sperma in the female is surplus blood collected in the uterus and not an ovum. I subsequently (...) argue that, for Aristotle, this blood does persist through the production of the fetus. (shrink)

Tun und Können erläutert und diskutiert den Gründungstext der Modalontologie: das neunte Buch der Metaphysik des Aristoteles. Aristoteles' Thesen und Argumente werden zum ersten Mal in Gänze mit formalen analytischen Mitteln rekonstruiert und auf ihre Kohärenz und Gültigkeit geprüft. Erstmals verwendet der Autor dazu eine adverbiale Analyse von Ausdrücken des Könnens und des Vermögens als Prädikatmodifikatoren. Das Buch zeigt, dass Aristoteles' Theorie der Vermögen nicht nur eine konsistente, sondern auch eine leistungsfähige Analyse von Dispositionen und Dispositionsprädikaten bietet. -/- Die Neuausgabe (...) wurde vollständig durchgesehen und um weiterführende Anhänge ergänzt. -/- Der Inhalt: Können, Tun und Möglichkeit. Eine Einführung • Die kausale Dimension von Vermögen • Die ontologische Dimension von Vermögen• Eine notwendige Bedingung für Vermögen • Hindernisse und Verwirklichung • Prioritätsfragen • Aristotle’s Theory of Dispositions • Das Problem des Neuen • Planners, Deciders, Performers. (shrink)