Alexander R. Pruss

One of the problems that Bayesian regularity, the thesis that all contingent propositions should be given probabilities strictly between zero and one, faces is the possibility of random processes that randomly and uniformly choose a number between zero and one. According to classical probability theory, the probability that such a process picks a particular number in the range is zero, but of course any number in the range can indeed be picked. There is a solution to this particular problem on the books: a measure that assigns the same infinitesimal probability to each number between zero and one. I will show that such a measure, while mathematically interesting, is pathological for use in confirmation theory, for the same reason that a measure that assigns an infinitesimal probability to each possible outcome in a countably infinite lottery is pathological. The pathology is that one can force someone to assign a probability within an infinitesimal of one to an unlikely event

There is an important sense in which one can be sure without being certain, i.e., without assigning unit probability. I will offer an explication of this sense of sureness, connecting it with the level of credence that a rational agent would need to have to be confident that she won’t ever lose her confidence. A simple formal result then gives us an explicit formula connecting the threshold α for credence needed for confidence with the threshold needed for being sure: one needs 1−(1−α) to be sure. I then suggest that stepping between α and 1−(1−α) gives a procedure that generates an interesting hierarchy of credential thresholds.

Adhering to the traditional concept of omniscience lands Gale in the incoherence Grim’s Cantorian arguments reveal in talk of “all propositions.” By constructing variants and extensions of Grim’s arguments, I explain why various ways out of the incoherence are unacceptable, why theists would do better to adopt a certain revisionary concept of omniscience, and why the Cantorian troubles are so deep as to be troubles as well for Gale’s Weak PSR. I conclude with some brief reflections on method, suggesting that we pursue the full implications of Gale’s own revisionary remarks and replace his method of analytic argumentation with non-analytic revisionary theory-construction.

Animalism is the view that we are animals and, thus, satisfy the criteria of identity proper to animals. This is highly plausible, for instance because it accepts at face value what appears to be the obvious facts that we are mammals—after all, we have the hair, the inner ear bones and the milk that mammals do—and that being a mammal is a way of being an animal. On the main opposing view, one has to hold that associated with each of us there are two entities: a person and an animal, of which we are only one, and this seems needlessly..

Substantive theories of diachronic identity have been offered for different kinds of entities. The kind of entity whose diachronic identity has received the most attention in the literature is person, where such theories as the psychological theory, the body theory, the soul theory, and animalism have been defended. At the same time, Wittgenstein's remark that ?to say of two things that they are identical is nonsense, and to say of one thing that it is identical with itself is to say nothing at all? suggests that the idea of further analysing identity is mistaken at root. I shall offer a simple, deflationary theory that reduces diachronic identity to quantification, synchronic identity and existence at a spacetime location (or at a time, for non-spatial entities). On logical grounds, the theory is guaranteed to have no counterexamples. Because the theory is guaranteed to have no counterexamples, all the imaginative examples offered as intuitive support for theories of personal identity are going to be either incorrect or compatible with the theory. I shall argue that the deflationary theory is preferable on simplicity grounds to typical substantive theories, and that various problems that are commonly thought to concern diachronic identity are better seen as about something else

Let S be the set of all entities that exist (or have existed). Define the relation <= on S by saying that x<=y if and only y is a cause of x. By verbal fiat we will define x to be a cause of x for all x in S (if we do not accept this definition, our assumptions will be slightly different; however, it is clear that the existence of x is necessary and sufficient for the existence of x, and that the existence of x is never strictly temporally posterior to that of x, so calling x a cause of itself is not such a bad idea.) Then, <= is transitive, and moreover if x<=y and y<=x, then x=y (i.e., there are no circles of causation). Hence, <= defines a partial ordering on S.

We will give a new cosmological argument for the existence of a being who, although not proved to be the absolutely perfect God of the great Medieval theists, also is capable of playing the role in the lives of working theists of a being that is a suitable object of worship, adoration, love, respect, and obedience. Unlike the absolutely perfect God, the God whose necessary existence is established by our argument will not be shown to essentially have the divine perfections of omnipotence, omniscience, omnibenevolence, and sovereignty. Furthermore, it is not even shown that he is contingently omnipotent and omniscient, just powerful and intelligent enough to be the supernatural designer-creator of the exceedingly complex and wondrous cosmos that in fact..

The production of a number of vaccines involves the use of cell-lines originally derived from fetuses directly aborted in the 1960s and 1970s. Such cell-lines, indeed sometimes the very same ones, are important to on-going research, including at Catholic institutions. The cells currently used are removed by a number of decades and by a significant number of cellular generations from the original cells. Moreover, the original cells extracted from the bodies of the aborted fetuses were transformed to produce the cell lines, since otherwise they would be incapable of the kind of culturing that is required.

Louis Pojman has argued that Christian faith does not entail belief, or even assigning a probability of 1/2 to the claims of Christianity. However, this conclusion fails in many cases because of its ethical consequences. A Christian is committed by his faith to acting in accordance with Christian teaching. However, there are circumstances when it is morally impermissible to act in accordance to beliefs to which one assigns epistemic probability smaller than 1/2, namely when the action is prohibited by ethical claims that one takes to be more probable. It is argued that in most cases such considerations preclude a person who assigns a probability of less 1/2 from being both committed both to Christianity and to the moral life. Matters are particularly clear in the paradigmatic faith-action of Abraham’s sacrifice of Isaac: this action would clearly be immoral if Abraham assigned a probability less than 1/2, or in fact any probability not very close to 1, to the existence of God. A moral version of Pascal’s wager is also discussed.

There is a long tradition of arguments for the existence of God. Early examples include Aristotle’s cosmological argument in Book Lambda of the Metaphysics, arguing that if there is change, there must be at least one unchanging and perfect being that originates all change, while the first chapter of Romans and chapter 13 of the Book of Wisdom insist that “from the greatness and the beauty of created things their original author, by analogy, is seen” (Wis. 13:5, NAB). This tradition continues, and indeed starting in the 1950s, analytic philosophy has seen an impressive resurgence of more and more careful formulations and criticisms of arguments for the existence of God. I shall show how the phenomenon of altruism yields a theistic argument. Some arguments for the existence of God proceed by pure reasoning alone and yield ontological arguments like Anselm’s, while others depend in part either on particular empirical claims (e.g., the argument from miracles or the argument from religious experience), or on general empirical claims, such as that there is motion, consciousness or life. The pattern of the arguments based on general claims is usually simple: (A) There is a general fact about reality, say that there is change or that there are complex organisms. (B) One argues that either the best or the only explanation is to be found in some state of affairs that includes the existence of a God-like being. And so (C) one concludes that a God-like being..

In simplified form, the argument that I am defending holds that the incompatibility of our freedom with determinism follows from the conjunction of (1) a plausible supervenience claim which says that whether a human agent is free depends only on what happens during the agent’s life and (2) a freedom-cancellation principle of Richard Gale which says that an agent is not free if all of her actions are intentionally brought about by another agent. Improved versions of (1) and (2) are also considered

The Principle of Sufficient Reason says that all contingent facts must have explanation. In this 2006 volume, which was the first on the topic in the English language in nearly half a century, Alexander Pruss examines the substantive philosophical issues raised by the Principle Reason. Discussing various forms of the PSR and selected historical episodes, from Parmenides, Leibnez, and Hume, Pruss defends the claim that every true contingent proposition must have an explanation against major objections, including Hume's imaginability argument and Peter van Inwagen's argument that the PSR entails modal fatalism. Pruss also provides a number of positive arguments for the PSR, based on considerations as different as the metaphysics of existence, counterfactuals and modality, negative explanations, and the everyday applicability of the PSR. Moreover, Pruss shows how the PSR would advance the discussion in a number of disparate fields, including meta-ethics and the philosophy of mathematics.

This article focuses on the question of whether the doctrine of the real presence of Christ's body and blood, and likewise the doctrine of the real absence of bread and wine, can be defended philosophically. It argues for an affirmative answer, and does so by considering a variety of metaphysical models, including that of Aquinas. It will appear, thus, that transubstantiation is a philosophical possibility. If it is possible for two substances to be in the same place at the same time, consubstantiation will be a philosophical possibility as well. Of course, the question of actuality is a theological one.