The Principle of Sufficient Reason is very seldom, if ever, referred to in the works of whom we might think of as the eminent Asian metaphysicians. In spite of this, the big picture metaphysical views available in the thought of philosophers such as Nāgārjuna, Fazang and Nishida appear to share certain structural features with views more familiar to us from our own tradition; views that explicitly accept or reject the Principle of Sufficient Reason. Nāgārjuna (...) looks to develop a kind of metaphysical infinitism, Fazang an extreme form of coherentism, and Nishida a species of foundationalism. These three positions - infinitism, coherentism and foundationalism - are typically thought to exhaust the spread of possibilities by those working within the Western tradition. -/- In spite of their similarities to positions advanced within our own tradition, the cosmologies of many of the giants of Asian philosophy are characterised by their rather striking conclusions. Amongst such conclusions for Nāgārjuna is that everything is empty; for Fazang that everything is identical to everything else; and for Nishida that everything depends on absolute nothingness. If the Principle of Sufficient Reason is playing a role in the derivation of such striking conclusions, then it looks that there are more options regarding the metaphysical structure of the world available to us than our own tradition typically courts. If, on the other hand, these striking cosmological conclusions are arrived at without any consideration of sufficient reason, then there may well be ways of reasoning about the overarching structure of reality that are powerful but unfamiliar to Western thinking. In this contribution, I explore what, if any, role the PSR might be playing in the thought of Nāgārjuna , Fazang and Nishida, and what we might be able to learn from it. (shrink)

The Clarke/Rowe version of the Cosmological Argument is sound only if the Principle of Sufficient Reason is true, but many philosophers, including Rowe, think that there is not adequate evidence for the principle of sufficient reason. I argue that there may be indirect evidence for PSR on the grounds that if we do not accept it, we lose our best justification for an important principle of metaethics, namely, the Principle of Universalizability. To (...) show this, I argue that all the other justifications of the Principle of Universalizability on offer, including Richard Hare's, are inadequate. (shrink)

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. (shrink)

According to the Principle of Sufficient Reason (henceforth ‘PSR’), everything has an explanation or sufficient reason. This paper addresses three questions. First, how continuous is the contemporary notion of grounding with the notion of sufficient reason endorsed by Spinoza, Leibniz, and other rationalists? In particular, does a PSR formulated in terms of ground retain the intuitive pull and power of the PSR endorsed by the rationalists? Second, to what extent can the PSR avoid (...) the formidable traditional objections levelled against it if it is formulated in terms of ground? And finally, how might historical discussion of the PSR shed light on the contemporary notion of grounding? (shrink)

Peter van Inwagen presented a powerful argument against the Principle of Sufficient Reason, which I henceforth abbreviate as ‘PSR’. For decades, the consensus was that this argument successfully refuted PSR. However, now a growing consensus holds that van Inwagen’s argument is fatally flawed, at least when ‘sufficient reason’ is understood in terms of ground, for on this understanding, an ineliminable premiss of van Inwagen’s argument is demonstrably false and cannot be repaired. I will argue that (...) this growing consensus is mistaken and that a powerful argument relevantly similar to van Inwagen’s should still concern us, even when we understand ‘sufficient reason’ in terms of ground. (shrink)

The Principle of Sufficient Reason is a powerful and controversial philosophical principle stipulating that everything must have a reason or cause. This simple demand for thoroughgoing intelligibility yields some of the boldest and most challenging theses in the history of metaphysics and epistemology. In this entry we begin with explaining the Principle, and then turn to the history of the debates around it. A section on recent discussions of the Principle will be added (...) in the near future. (shrink)

Alexander Pruss’s Principle of Sufficient Reason states that every contingent true proposition has an explanation. Pruss thinks that he can plausibly maintain both his PSR and his account of libertarian free will. This is because his libertarianism has it that contingent true propositions reporting free choices are self-explanatory. But I don’t think Pruss can plausibly maintain both his PSR and libertarianism without a rift occurring in one or the other. Similar to the old luck/randomness objection, I contend (...) that Pruss’s libertarianism is susceptible to what I call “the inexplicability objection”, which attempts to show that agents’ free choices involve contingent brute facts. Pruss may be able to partially explain a proposition such that Jones freely chose A for reason R, but he cannot adequately explain a contrastive proposition such as that Jones freely chose A for R rather than B for R*. The result is that either PSR is too explanatorily permissive for libertarianism, or libertarianism is too explanatorily impermissive to satisfy PSR. After considering what I take to be Pruss’s best response to the inexplicability objection, I conclude that his attempt to reconcile PSR and libertarianism is unsuccessful. (shrink)

Toward the end of his classic treatise An Essay on Free Will, Peter van Inwagen offers a modal argument against the Principle of Sufficient Reason which he argues shows that the principle “collapses all modal distinctions.” In this paper, a critical flaw in this argument is shown to lie in van Inwagen’s beginning assumption that there is such a thing as the conjunction of all contingently true propositions. This is shown to follow from Cantor’s theorem and (...) a property of conjunction with respect to contingent propositions. Given the failure of this assumption, van Inwagen’s argument against the Principle of Sufficient Reason cannot succeed, at least not without the addition of some remarkable and previously unacknowledged qualifications. (shrink)

I examine Leibniz’s version of the Principle of Sufficient Reason with respect to free will, paying particular attention to Peter van Inwagen’s argument that this principle leads to determinism. Ultimately I conclude that Leibniz’s formulation is incompatible with free will. I then discuss a reformulation of the Principle of Sufficient Reason endorsed by Alexander Pruss that, I argue, manages to both retain the strength of Leibniz’s formulation and remain consistent with free will.

Kant's attack on metaphysics consists in large part in his attack on a principle that he names the Supreme Principle of Pure Reason. This principle, it is not often noticed, is the Principle of Sufficient Reason [PSR]. In interpreting this principle as such, I argue that Kant's attack on the PSR depends on Kant's claim that existence is not a first-order predicate. If existence isn't what Kant calls a real predicate, the PSR (...) is false. While this constitutes a powerful Kantian argument against dogmatic rationalism, it also poses a problem for Kant. For, as I argue, if the PSR is true, Kant's argument that existence isn't a first-order predicate is false. In this sense, Kant's attack on the PSR is begging the question vis-á-vis radical metaphysicians. Concluding the paper I suggest relying on Kant's 'is'/'ought' distinction in avoiding this circularity, thereby reinforcing the Kantian critique. (shrink)

The paper is about the physical theories which result when one identifies points in phase space related by symmetries; with applications to problems concerning gauge freedom and the structure of spacetime in classical mechanics.

Leibniz, and many following him, saw the Principle of Sufficient Reason (PSR) as pivotal to a scientific (demonstrated) metaphysics. Against this backdrop, Kant is expected to pay close attention to PSR in his reflections on the possibility of metaphysics, which is his chief concern in the Critique of Pure Reason. It is far from clear, however, what has become of PSR in the Critique. On one reading, Kant has simply turned it into the causal principle (...) of the Second Analogy. On a different reading, PSR is but the supreme principle of reason, which roughly states that, if the conditioned is given, so is the unconditioned. On my reading, PSR appears in the guises of both the causal principle and the supreme principle. This twofold specification, I argue, is key to understanding (i) Kant’s allegations that past metaphysicians failed to prove PSR, (ii) his own Critical account of the possibility of metaphysics in both of its parts (ontology and metaphysics proper), and (iii) his nuanced answer to the contentious question about the relation between physical inquiry and metaphysical reasoning about nature (both being quests for reasons). (shrink)

Whether or not the principle of sufficient reason is a fundamental rule of formal logic is a question that merits serious discussion. In debates from as early as the 1960s, when discussing the subject and functions of formal logic, some comrades pointed out that formal logic cannot study just the forms of thought alone. One of their basic arguments was that "the principle of sufficient reason demands that the content of a premise must be (...) true." In discussions concerning the truth and validity of formal logic, some comrades likewise suggested that the validity of thought forms and the truth of their content were identical, their reason being that "one of the demands of the principle of sufficient reason is that a reason must be true." These discussions have already touched on the question of the nature of the principle of sufficient reason. Thus, this discussion now under way is a continuation and deepening of the past discussions on logic. Not only does it involve the content of the principle of sufficient reason and its role and function in formal logic, it also involves the object of study and the direction of the future development of this science, formal logic. The discussion of this problem is undoubtedly highly significant. (shrink)

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be (...) preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. (shrink)

I argue that Émilie Du Châtelet breaks with Christian Wolff regarding the scope and epistemological content of the principle of sufficient reason, despite his influence on her basic ontology and their agreement that the principle of sufficient reason has foundational importance. These differences have decisive consequences for the ways in which Du Châtelet and Wolff conceive of science.

According to Principles of Sufficient Reason, every truth (in some relevant group) has an explanation. One of the most popular defenses of Principles of Sufficient Reason has been the presupposition of reason defense, which takes endorsement of the defended PSR to play a crucial role in our theory selection. According to recent presentations of this defense, our method of theory selection often depends on the assumption that, if a given proposition is true, then it has (...) an explanation, and this will only be justified if we think this holds for all propositions in the relevant group. I argue that this argument fails even when restricted to contingent propositions, and even if we grant that there is no non-arbitrary way to divide true propositions that have explanations from those that lack them. Further, we can give an alternate explanation of what justifies our selecting theories on the basis of explanatory features: the crucial role is not played by an endorsement of a PSR, but rather by our belief that, prima facie, we should prefer theories that exemplify explanatory power to greater degrees than their rivals. This guides our theory selection in a manner similar to ontological parsimony and theoretical simplicity. Unlike a PSR, our belief about explanatory power gives us a prima facie guiding principle, which provides justification in the cases where we think we have it, and not in the cases where we think we don't. (shrink)

The Clarke/Rowe version of the Cosmological Argument is sound only if the Principle of Sufficient Reason (PSR) is true, but many philosophers, including Rowe, think that there is not adequate evidence for the principle of sufficient reason. I argue that there may be indirect evidence for PSR on the grounds that if we do not accept it, we lose our best justification for an important principle of metaethics, namely, the Principle of Universalizability. (...) To show this, I argue that all the other justifications of the Principle of Universalizability on offer, including Richard Hare's, are inadequate. (shrink)

Ismay Barwell, Kathleen Lennon; II*—The Principle of Sufficient Reason, Proceedings of the Aristotelian Society, Volume 83, Issue 1, 1 June 1983, Pages 19–34, h.

The Principle of Sufficient Reason must be justified dialectically: by showing the disastrous consequences of denying it. We formulate a version of the Principle that is restricted to basic natural facts, which entails the obtaining of at least one supernatural fact. Denying this principle results in extreme empirical skepticism. We consider six current theories of empirical knowledge, showing that on each account we cannot know that we have empirical knowledge unless we all have a priori (...) knowledge of the PSR. We consider objections based on Neo-Humeanism and the essentiality of origins, and we consider the possibility that we have empirical knowledge without knowing it. (shrink)

I distinguish three ways in which early modern rationalists seek to apply the principle of sufficient reason to empirical science, and critically assess some of their attempts to do so. I focus especially on how these thinkers assume substantive theories of explanation and intelligibility--which are indebted to the mechanist and experimentalist traditions--in many of their deployments of this rationalist principle. A recurring problem is that these philosophers deploy their standards of intelligibility inconsistently: some of their own (...) favored explanations do not always live up to their standards. I argue that the problem is especially acute for Leibniz and Euler, given their enthusiasm for final-causal explanations. (shrink)

The term “principle of sufficient reason” (PSR) was coined by Leibniz, and he is often regarded as its paradigmatic proponent. But as Leibniz himself often insisted, he was by no means the first philosopher to appeal to the idea that everything must have a reason. Histories of the principle attribute versions of it to various ancient authors. A few of these studies include—or at least do not exclude—medieval philosophers; one finds the PSR in Abelard, another (...) finds it in Aquinas. And while Leibniz retains pride of place in these histories, Spinoza is sometimes said to precede him “in appreciating the importance of the Principle and placing it at the center of his philosophical system.” In this paper, the author argues that the same should be said of the Islamic philosopher Avicenna. Writing 600 years before his early modern counterparts, Avicenna routinely and consistently appeals to the PSR in generating his metaphysical system. The paper aims first to establish that Avicenna deserves a position of prominence in histories of the PSR, and then to consider how he addresses certain challenges to the PSR, especially the threat posed by necessitarianism. (shrink)

The principle of sufficient reason threatens modal collapse. Some have suggested that by appealing to the indefinite extensibility of contingent truth, the threat is neutralized. This paper argues that this is not so. If the indefinite extensibility of contingent truth is developed in an analogous fashion to the most promising models of the indefinite extensibility of the concept set, plausible principles permit the derivation of modal collapse.

Des philosophes théistes comme Thomas D. Sullivan ont adapté les arguments cosmologiques bases sur le Principe de raison suffisante pour les ajuster à la cosmologie contemporaine du Big Bang Leur thèse centrale est que uisque le Big Bang n'a pas pu avoir une cause physique et puisque tout a une cause, le Big Bang a dû avoir une cause non physique ou surnaturelle. Des philosophes non théistes qui acceptent la cosmologie standard du Big Bang ont remis en question la vérité (...) de PRS, en soutenant que certains événements peuvent se produire sans aucune cause. Quentin Smith a défendu l'idée que PRS n'est pas du tout évident par lui-meme et qu'il y a en fait de bonnes raisons de supposer que des choses comme des singularites peuvent se produire sans cause. Thomas D. Sullivan a répliqué à l'argument de Smith voulant que PRS ne soit pas évident par lui-même, et il afourni en outre une pretendue preuve de PRS. Je soutiens dans cet article que PRS, en réalité, n'est pas évident par soi-même et que l'argument de Sullivan en faveur du contraire repose sur un malentendu quant à ce que nous entendons généralement pas «évident par lui-même». J'essaie également de montrer que la preuve de PRS fournie par Sullivan souffre de nombreuses difficultés. Si j'ai raison sur tout cela le PRS nest pas evident par lui-même et nous ne disposons d'aucun argument en safaveur. Il n'en découle pas que PRS soit faux, mais il en découle que nous sommes justifiés de ne pas être convaincus par les arguments en faveur de l'existence de Dieu qui prennent PRS pour prémisse. (shrink)

This essay examines arguments offered in support of the Principle of Sufficient Reason (PSR) by Leibniz and his followers as well as Hume's critique of the PSR. It is shown that Leibniz has a defensible argument for the PSR, whereas the arguments of his self-proclaimed followers are weak. Thus, Hume's challenge is met by Leibniz, by Wolff and Baumgarten not so much.

I show how the Cosmological Argument (CA) is undermined by one of its own premises: the Principle of Sufficient Reason (PSR). First, I explain the type of CA that I am thinking about. Second, I explain a traditional modal objection against the PSR, which is ultimately based upon our intuitions in favor of contingency. Third, I show how this modal objection begs the question against the necessitarian, and then I reformulate the CA in more neutral terms. Fourth, (...) using this more neutral version of the CA, I argue that the main problem with the PSR goes way beyond its apparent necessitarian consequences. As an argument used by Bradley shows, embracing the rationalist path that underlies the PSR seems to commit us to a form of Radical Monism. I conclude by showing how this result ultimately undermines the CA. (shrink)

According to the unrestricted version of the Principle of Sufficient Reason (PSR), every truth has an explanation. I argue that there is defeasible methodological justification for belief in an unrestricted PSR. The argument is based on considerations about our cognitive limitations. It is possible that our cognitive limitations prevent us from even recognizing the explanatorily open character of some propositions we can now represent: the fact that these propositions are explicable in the first place. If this is (...) the case, then a proper recognition of our limitations and a standing goal of reasoning to attain complete explanatory knowledge justify the adoption of an unrestricted PSR. (shrink)

This essay argues for the contingency of necessity. The thesis is that contingency constitutes the possibility of necessity, which is always subsequent to contingency, only contingent necessity, a mere modality of contingent being. This study posits the contingency of necessity through a reading of Quentin Meillassoux and the late lectures of F. W. J. Schelling. While Meillassoux argues for the necessity of contingency, Schelling seeks to uncover the contingency at the heart of what is necessary. Although the principle of (...) sufficient reason provides the necessary conditions for something and reason itself derives necessary truths, the fact that there is reason rather than unreason is but the contingency of a fact. (shrink)

Outlines a conceptual argument against the Principle of Sufficient reason. The argument is presented in detail in earlier work, and is based on deductive inferences from PSR's own concept of explanation. The argument shows that not everything can have an explanation of the sort claimed by PSR. So far from being a presupposition of reason itself, as some think, PSR can be refuted by reason, arguing only from PSR's own concept of explanation. Hence PSR cannot (...) be used to argue that there must be some explanation or reason for existence, invisible at least to science, or that because we do not or cannot know the explanation, there must be irreducible mystery about why there is anything at all rather than nothing, including why there was a Big Bang in the first place. (shrink)

In a recent article published in this journal, Kris McDaniel proposes a variant of Peter van Inwagen’s argument against the principle of sufficient reason that makes crucial use of plural grounding. In this response paper I object to McDaniel’s argument. I argue that there is no notion of plural grounding available that is both irreflexive in the sense required for the argument to go through and general enough to formulate the principle of sufficient reason (...) as proposed by McDaniel. (shrink)

This paper defends the Principle of Sufficient Reason, taking Baumgarten as its guide. The primary aim is not to vindicate the principle, but rather to explore the kinds of resources Baumgarten originally thought sufficient to justify the PSR against its early opponents. The paper also considers Baumgarten’s possible responses to Kant’s pre-Critical objections to the proof of the PSR. The paper finds that Baumgarten possesses reasonable responses to all these objections. While the paper notes that (...) in the absence of a response to Kant’s Critical discussion of the PSR, this result does not vindicate the principle, it shows how this discussion provides a deeper understanding of what, according to Baumgarten, the PSR really assumes and intends, and prepares the way for a more responsible discussion of Kant’s critical objections to Baumgarten’s supposed proof. (shrink)

reality is a complex affair. It comprises a huge variety of different elements. Importantly, though, reality is not a mere aggregate of its elements but rather a structured whole or system whose building blocks are not all on the same level. Instead, they form hierarchical networks ordered by relations of priority. In such networks, derivative aspects of reality obtain in virtue of their grounds, that is, in virtue of more fundamental aspects of reality that are prior to them.This picture of (...) reality as a structured whole is currently enjoying a renaissance in the works of philosophers such as Kit Fine, Jonathan Schaffer, and many others. But far from being a new picture, it has been widely endorsed throughout the... (shrink)

The Principle of Sufficient Reason —the principle that everything has a reason—plays a central role in Leibniz’s philosophical system. It is rather difficult, however, to determine what Leibniz’s attitude towards the modal status of the PSR is. The prevailing view is that Leibniz takes the PSR to be true necessarily. This paper develops a novel interpretation and argues that Leibniz’s PSR is a contingent principle. It also discusses whether a merely contingent PSR can do (...) the metaphysical heavy lifting that Leibniz aims for. The paper shows that, despite appearance to the contrary, this is possible. In a nutshell, the argument is that the only possible PSR violation Leibniz allows for is God’s creation of a suboptimal world; there is no Leibnizian possible world, though, which intrinsically violates the PSR. Despite its contingency, then, Leibniz’s PSR is modally robust enough to serve as a foundational principle of his metaphysics. (shrink)

Leibniz often refers to the Principle of Sufficient Reason (PSR) as something like a first principle. In some texts, however, he attempts to give positive arguments in its favor. I examine two such arguments, and find them wanting. The first argument has two defects. First, it is question-begging; and second, when the question-begging step is excised, the principle one can in fact derive is highly counter-intuitive. The second argument is valid, but has the defect of (...) only reaching a nearly trivial conclusion. (shrink)

This little-known work by the famous German pessimist and critic of Hegel was originally written as a doctoral dissertation when Schopenhauer was just twenty-six, but it was later revised when the philosopher was sixty. So important did he consider this work, originally titled "On the Fourfold Root of the Principle of Sufficient Reason," that he often underscored the fact that no one could hope to understand his magnum opus, The World as Will and Representation, without having first (...) read this work. Schopenhauer takes up where Kant left off in response to Hume, and his insights into the nature of perception and understanding remain amazingly relevant and still unsurpassed. Schopenhauer's analyses of causation and related concepts rival and probably surpass in their depth and brilliance the more celebrated discussions of David Hume. Where Hume grossly oversimplified these problems and left them riddled with paradoxes, Schopenhauer disentangled them and shed light on what had seemed hopelessly dark. (shrink)

‘The Principle of Sufficient Reason in all its forms is the sole principle and the sole support of all necessity. For necessity has no other true and distinct meaning than that of the infallibility of the consequence when the reason is posited. Accordingly every necessity is conditioned; absolute, i.e. unconditioned, necessity therefore is a contradicto in adjecto. For to be necessary can never mean anything but to result from a given reason.’ These words are (...) taken from the beginning of section 49 of Schopenhauer's The Fourfold Root of the Principle of Sufficient Reason. They express sentiments with which I am to some extent in agreement, and it therefore seemed to me worth while to explore in some kind of detail Schopenhauer's treatment of the issues. It might, however, be asked why the view expressed by Schopenhauer should be of philosophical interest, what, if anything, turns on the rejection of the notion of absolute necessity. To this I can reply by saying only that apart from the intrinsic interest of the notion of necessity itself, an issue on which a philosopher ought to make himself clear, Schopenhauer himself points to some of the consequences of his doctrine - the impossiblity, for example, of an absolutely necessary being, and the similar impossibility of ontological or cosmological arguments. (shrink)