Reasoning Without the Principle of Sufficient Reason

Faith and Philosophy, 2010

The Principle of Sufficient Reason (PSR) says that all contingent facts must have explanations. In this volume, the first on the topic in the English language in nearly half a century, Alexander Pruss examines the substantive philosophical issues raised by the PSR, which currently is considered primarily within the context of various cosmological arguments for the existence of God. Discussing several forms of the PSR and selected historical episodes from Parmenides, Aquinas, Leibniz, Hume, and Kant, 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, such as metaethics and the philosophy of mathematics.

Two New Objections to Explanationism

After a period of inactivity, interest in explanationism as a thesis about the nature of epistemic justification has been renewed. Ted Poston (2014) and Kevin McCain (2014) have both recently offered versions of explanationist evidentialism. In this paper, we pose two objections to explanationist evidentialism. First, explanationist evidentialism fails to state a sufficient condition for justification. Second, explanationist evidentialism implies a vicious regress.

Bloomsbury Academic eBooks, 2017

The Principle of Sufficient Reason (PSR) says that all contingent facts must have explanations. In this volume, the first on the topic in the English language in nearly half a century, Alexander Pruss examines the substantive philosophical issues raised by the PSR, which currently is considered primarily within the context of various cosmological arguments for the existence of God. Discussing several forms of the PSR and selected historical episodes from Parmenides, Aquinas, Leibniz, Hume, and Kant, 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, such as metaethics and the philosophy of mathematics.

Faith and Philosophy, 1993

Stanford Encyclopedia of Philosophy, 2010

The Principle of Sufficient Reason (PSR) says that, necessarily, every contingently true proposition has an explanation. The PSR is the most controversial premise in the cosmological argument for the existence of God. It is likely that one reason why a number of philosophers reject the PSR is that they think there are conceptual counterexamples to it. For instance, they may think, with Peter van Inwagen, that the conjunction of all contingent propositions cannot have an explanation, or they may believe that quantum mechanical phenomena cannot be explained. It may, however, be that these philosophers would be open to accepting a restricted version of the PSR as long as it was not ad hoc. I present a natural restricted version of the PSR that avoids all conceptual counterexamples , and yet that is strong enough to ground a cosmological argument. The restricted PSR says that all explainable true propositions have explanations.

2010

Comparisons of rival explanations or theories often involve vague appeals to explanatory power. In this paper, we dissect this metaphor by distinguishing between different dimensions of the goodness of an explanation: non-sensitivity, cognitive salience, precision, detail, factual accuracy and degree of integration. These dimensions are partially independent and often come into conflict. Our main contribution is to go beyond simple stipulation or description by explicating why these factors are taken to be explanatory virtues in the first place. We accomplish this by using the contrastive-counterfactual approach to explanation and the view of understanding as an inferential ability. By combining these perspectives, we show how the explanatory power of an explanation in a given dimension can be assessed by showing the range of answers it provides to what-if-things-had-been-different questions and the theoretical and pragmatic importance of these questions. We also show how our account explains intuitions linking explanation to unification or to the exhibition of a mechanism.

We argue that there is no general theory of explanation that spans the sciences, mathematics, and ethics, etc. More specifically, there is no good reason to believe that substantive and domain-invariant constraints on explanatory information exist. Using Nickel (Noûs 44(2):305–328, 2010) as an exemplar of the contrary, generalist position, we first show that Nickel’s arguments rest on several ambiguities, and then show that even when these ambiguities are charitably corrected, Nickel’s defense of general theories of explanation is inadequate along several different dimensions. Specifically, we argue that Nickel’s argument has three fatal flaws. First, he has not provided any compelling illustrations of domain-invariant constraints on explanation. Second, in order to fend off the most vehement skeptics of domain-invariant theories of explanation, Nickel must beg all of the important questions. Third, Nickel’s examples of explanations from different domains with common explanatory structure rely on incorrect formulations of the explanations under consideration, circular justifications, and/or a mischaracterization of the position Nickel intends to critique. Given that the best and most elaborate defense of the generalist position fails in so many ways, we conclude that the standard practice in philosophy (and in philosophy of science in particular), which is to develop theories of explanation that are tailored to specific domains, still is justified. For those who want to buy into a more ambitious project:beware of the costs!

Episteme, 2013

In their most recent co-authored work Earl Conee and Richard Feldman (2008) suggest that epistemic support should be understood in terms of best explanations. Although this suggestion is plausible, Conee and Feldman admit that they have not provided the necessary details for a complete account of epistemic support. This paper offers an explanationist account of epistemic support of the kind that Conee and Feldman suggest. It is argued that this account of epistemic support yields the intuitively correct results in a wide variety of cases. Further, this explanationist account of epistemic support is not susceptible to objections Keith and Alvin Goldman (2011) have raised for similar accounts of epistemic support.

Metascience, 2022

In his recent book, John Norton has created a theory of inference to the best explanation, within the context of his "material theory of induction". I apply it to the problem of scientific explanations that are false: if we want the theories in our explanations to be true, then why do historians and scientists often say that false theories explained phenomena? I also defend Norton's theory against some possible objections.