Search

Eells and Sober proved in 1983 that screening off is a sufficient condition for the transitivity of probabilistic causality, and in 2003 Shogenji noted that the same goes for probabilistic support. We start this paper by conjecturing that Hans Reichenbach may have been aware of this fact. Then we consider the work of Suppes and Roche, who demonstrated in 1986 and 2012 respectively that screening off can be generalized, while still being sufficient for transitivity. We point out an interesting difference between Reichenbach’s screening off and the generalized version, which we illustrate with an example about haemophilia among the descendants of Queen Victoria. Finally, we embark on a further generalization: we develop a still weaker condition, one that can be made as weak as one wishes.

In a recent paper Ronald Meester and Timber Kerkvliet argue by example that infinite epistemic regresses have different solutions depending on whether they are analyzed with probability functions or with belief functions. Meester and Kerkvliet give two examples, each of which aims to show that an analysis based on belief functions yields a different numerical outcome for the agent’s degree of rational belief than one based on probability functions. In the present paper we however show that the outcomes are the same. The only way in which probability functions and belief functions can yield different solutions for the agent’s degree of belief is if they are applied to different examples, i.e. to different situations in which the agent finds himself.

InA Treatise of Human Nature, David Hume presents an argument according to which all knowledge reduces to probability, and all probability reduces to nothing. Many have criticized this argument, while others find nothing wrong with it. In this paper we explain that the argument is invalid as it stands, but for different reasons than have been hitherto acknowledged. Once the argument is repaired, it becomes clear that there is indeed something that reduces to nothing, but it is something other than what, according to many, Hume had in mind. Thus two views emerge of what exactly it is that reduces. We surmise that Hume failed to distinguish the two, because he lacked the formal means to differentiate between a rendering of his argument that is in accordance with the probability calculus, and one that is not.

In August 2015 the Faculty of Philosophy in Groningen hosted JustGroningen, a three-day conference on epistemic justification. The event was funded by the Netherlands Organisation of Scientific Research (NWO) as part of a project on infinite regresses in epistemology in which both of us are involved (Project Number 360-20-280).The present special issue sprang from this conference. It contains some papers that were presented there together with some others. We are very happy to have been able to bring together a collection that highlights so many different aspects of epistemic justification, and uses such a variety of methods to explore them.

The original article has been corrected. Erroneously, a comma and a space were added in line 164 to 500, 500, and the authors would like readers to know that this should instead read 500,500.

Tom Stoneham put forward an argument purporting to show that coherentists are, under certain conditions, committed to the conjunction fallacy. Stoneham considers this argument a reductio ad absurdum of any coherence theory of justification. I argue that Stoneham neglects the distinction between degrees of confirmation and degrees of probability. Once the distinction is in place, it becomes clear that no conjunction fallacy has been committed.

Richard Jeffrey's radical probabilism ('probability all the way down') is augmented by the claim that probability cannot be turned into certainty, except by data that logically exclude all alternatives. Once we start being uncertain, no amount of updating will free us from the treadmill of uncertainty. This claim is cast first in objectivist and then in subjectivist terms.

It is argued that the recent revival of theakrasia problem in the philosophy of mind is adirect, albeit unforeseen result of the debate onaction explanation in the philosophy of science. Asolution of the problem is put forward that takesaccount of the intimate links between the problem ofakrasia and this debate. This solution is basedon the idea that beliefs and desires have degrees ofstrength, and it suggests a way of giving a precisemeaning to that idea. Finally, it is pointed out thatthe solution captures certain intuitions of bothSocrates and Aristotle.

We have never entirely agreed with Daniel Cohnitz on the status and r?le of thought experi ments. Several years ago, enjoying a splendid lunch together in the city of Ghent, we cheer fully agreed to disagree on the matter; and now that Cohnitz has published his considered opinion of our views, we are glad that we have the opportunity to write a rejoinder and to explicate some of our disagreements. We choose not to deal here with all the issues that Cohnitz raises, but rather to restrict ourselves to three specific points. The first point concerns the way in which Cohnitz represents our views. He summa rizes them in five theses, (PA1)-(PA5), and while we have no dispute with the wording of (PA1)-(PA4), we consider (PA5) to be somewhat misleading. Putting into our mouths the declamation that "In philosophy we cannot turn to crucial experiments (whereas in science we can)" wrongly suggests that we take crucial experiments to constitute the pivotal difference between philosophy and science. At no place do we claim that disputes over thought experi ments in physics are always settled by carrying out a crucial experiment. Cohnitz writes: "As Peijnenburg and Atkinson seem to admit, this [the settling by a crucial experiment] is not the case for all physical thought experiments." Seem to admit? Nay, we roundly asseverate the fact! After that sentence, Cohnitz continues as follows

From 1929 onwards, C. I. Lewis defended the foundationalist claim that judgements of the form 'x is probable' only make sense if one assumes there to be a ground y that is certain (where x and y may be beliefs, propositions, or events). Without this assumption, Lewis argues, the probability of x could not be anything other than zero. Hans Reichenbach repeatedly contested Lewis's idea, calling it "a remnant of rationalism". The last move in this debate was a challenge by Lewis, defying Reichenbach to produce a regress of probability values that yields a number other than zero. Reichenbach never took up the challenge, but we will meet it on his behalf, as it were. By presenting a series converging to a limit, we demonstrate that x can have a definite and computable probability, even if its justification consists of an infinite number of steps. Next we show the invalidity of a recent riposte of foundationalists that this limit of the series can be the ground of justification. Finally we discuss the question where justification can come from if not from a ground.

Infinite regresses have had a mixed reception in philosophy. On the one hand, they are often quickly brushed aside as being unreasonable and even preposterous. If a position or a theory is shown to engender an infinite regress, that pretty well means the end of it: an argumentum ad infinitum is as good as a reductio ad absurdum. On the other hand, the alleged absurdity of infinite regresses has been a source of inspiration and the ground for far-reaching conclusions. It led to the requirement that a regress should come to a stop and thence to the verdict that there exist such things as a Prime Mover, a First Cause, a Highest Good, or a Causa Sui. Infinite regresses have been discussed in practically all branches of philosophy, not only in metaphysics and epistemology, but also in ethics, philosophy of mind, logic, and argumentation theory. In recent years, they have spurred a lively debate in traditional epistemology, where ‘infinitism’ (the idea that an infinite chain of epistemic justification is not prima facie absurd) is on its way to becoming a mature alternative to the traditional positions, foundationalism and coherentism. The papers in the present volume are about infinite regress in decision theory, philosophy of science, and formal epistemology. We are fortunate to have brought together a number of renowned philosophers and promising young scholars: John Barker is associate professor of Philosophy at the University of Illinois at Springfield, and chair of the Philosophy Department. His Ph.D. dissertation, defended in 1998 at Princeton University, is entitled ‘The Inconsistency Theory of Truth’. His areas of interest are philosophical logic and philosophy of language (especially paradoxes and inconsistencies) with side-interests in philosophy of mind and philosophy of science.

Kuipers’ model of action explanation is compared, first with that of Anscombe, and then with models in the post-Anscombian tradition. Whereas Kuipers and Anscombe differ on the question of the first-person view, the difference with post-Anscombian writers concerns the so-called intentional statement. Kuipers criticizes the models of both Hempel and von Wright for their lack of an intentional statement. Kuipers’ own model seems immune to this criticism, since it contains no less than two intentional statements, a “specific” and an “unspecific” one. I argue that, contrary to appearances, it is not so immune. The call for intentional statements is in fact a call for intentions that are irreducible to beliefs and desires. Kuipers’ intentional statements, however, are about intentions that can be so reduced.

This book is the second of two volumes devoted to the work of Theo Kuipers, a leading Dutch philosopher of science. Philosophers and scientists from all over the world, thirty seven in all, comment on Kuipers’ philosophy, and each of their commentaries is followed by a reply from Kuipers. The present volume is devoted to Kuipers’ neo-classical philosophy of science, as laid down in his Structures in Science (Kluwer, 2001). Kuipers defends a dialectical interaction between science and philosophy in that he views philosophy of science as a meta-science which formulates cognitive structures that provide heuristic patterns for actual scientific research, including design research. In addition, Kuipers pays considerable attention to the computational approaches to philosophy of science as well as to the ethics of doing research. Thomas Nickles, David Atkinson, Jean-Paul van Bendegem, Maarten Franssen, Anne Ruth Mackor, Arno Wouters, Erik Weber & Helena de Preester, Eric Scerri, Adam Grobler & Andrzej Wisniewski, Alexander van den Bosch, Gerard Vreeswijk, Jaap Kamps, Paul Thagard, Emma Ruttkamp, Robert Causey, Henk Zandvoort comment on these ideas of Kuipers, and many present their own account. The present book also contains a synopsis of Structures in Science. It can be read independently of the first volume of Essays in Debate with Theo Kuipers, which is devoted to Kuipers’ From Instrumentalism to Constructive Realism (2000).

SUMMARY. A characteristic of contemporary analytic philosophy is its ample use of thought experiments. We formulate two features that can lead one to suspect that a given thought experiment is a poor one. Although these features are especially in evidence within the philosophy of mind, they can, surprisingly enough, also be discerned insome celebrated scientific thought experiments. Yet in the latter case the consequences appear to be less disastrous. We conclude that the use of thought experiments is more successful in science than in philosophy.

This issue contains the papers presented at the conference Probability, Confirmation and Fallacies, which was held in the context of the Formal Epistemology Project in Leuven in April 2008. The conference was organized by Jeanne Peijnenburg with the assistance of David Atkinson and Ines Van Houtte. It was generously funded by the Government of the Flemish Community in Belgium, for which we would like to express our gratitude.