Perdurance

There has been a growing worry (raised in some form or another by Dean Zimmerman, Eric Olson, A.P. Taylor, Mark Johnston and Alex Kaiserman) that perdurantism—and similarly ontologically abundant views—is morally untenable. For perdurantism posits that, coinciding with persons, are person-like objects, and giving them their moral due seems to require giving up prudentially driven self-sacrifice. One way to avoid this charge is to adopt consequentialism. But Mark Johnston has argued that the marriage of consequentialism and perdurantism is in moral trouble. For, depending on the nature of time, consequentialist perdurantists either are unable to do more than one good act or they are morally obliged to adopt a repugnant form of ageism. I argue that perdurantist consequentialism doesn't have either repugnant implication.

En changeant, un objet présente successivement des propriétés incompatibles. Comment peut-il alors préserver son identité à travers le temps, condition sine qua non de son changement ?
Une première approche situe l’identité d’un tel objet qui change dans ce qui, en lui, est exempt de changement : une substance, une propriété ou encore une forme spatiale permanentes. Elle ne rend ainsi compte ni de l’identité de l’objet en tant qu’il change, ni, si le changement est essentiel au temps, de la temporalité constitutive de cette identité.
Une seconde approche soutient que, de même qu’un seul et même objet peut présenter simultanément des propriétés incompatibles si elles sont en différentes parties spatiales, il peut présenter successivement des propriétés incompatibles si elles sont en différentes parties temporelles. Un arbre peut changer, perdre ses feuilles, en ayant une partie temporelle estivale pendant laquelle il est feuillu, puis une autre, hivernale, pendant laquelle il est nu. Cependant, cette division de l’objet en différentes parties temporelles menace son unité à travers le temps.
Pour rendre compte à la fois de la temporalité et de l’unité d’un objet qui change, nous nous pencherons sur son rythme de changement, qui est à la fois constitué par ses changements et préservé tout au long de sa durée. Nous nous demanderons enfin si l’identité des objets qui changent de façon irrégulière peut être assurée de façon analogue.

Recent years have seen a revival of the idea that the entities existing in our world possess irreducible dispositions and powers by means of which they cause changes in the world. No longer being an outsider position, dismissible as obsolete and at odds with science, dispositional realism (‘dispositionalism’) has established itself as a viable and commonsensically appealing alternative to the hitherto predominant anti-realistic accounts of causation in the Humean tradition and, what is more, as a promising new approach to metaphysics in general.
In my talk, I shall take these latter ambitions seriously by exploring the implications of dispositionalism for persistence theory. Given that things have irreducible powers and dispositions, how ought we to think about the way they exist over time? In particular, should we assume they persist by being wholly present at different times (‘endurance) or rather by having different temporal parts (‘perdurance’)?
Dealing with two opposing proposals recently put forward by Stephen Mumford and Neil E. Williams, I will argue that the profile of ‘powerful’ persistence crucially depends on how one conceptualizes the processes involved in the manifestation of powers. As this is obviously not determined per se by subscribing to some view labelled ‘powers view’, further discussion is needed as to what processes are and to which kind of process theory a powers metaphysics should commit itself in order to be convincing.

Philosophers often state that the persistence of objects in vision is experienced differently than the persistence of sounds in audition. This difference is expressed by using metaphors from the metaphysical endurantism/perdurantism debate. For instance, it is claimed that only sounds are perceived as ''temporally extended''. The paper investigates whether it is justified to characterize visually experienced objects and auditorily experienced sounds as different types of entities: endurants and perdurants respectively. This issue is analyzed from the perspective of major specifications of the endurance/perdurance distinction connected, inter alia, with the notions of temporal parts and temporal localization. It is argued that it is unjustified to characterize visually experienced objects and auditorily experienced sounds as different types of entities in respect of how they persist. On the other hand, the apparent difference in the way of persisting can be explained by the presence of contingent differences between typical visual and auditory experiences.