At least since Aristotle’s famous ‘sea-battle’ passages in On Interpretation 9, some substantial minority of philosophers has been attracted to the doctrine of the open future—the doctrine that future contingent statements are never true. Such views, however, seem inconsistent with what John MacFarlane has called the determinacy intuition—the intuition, roughly, that if something has happened, then (looking backwards) it was the case that it would happen. This tension forms, in large part, what might be called the problem of future contingents. (...) A dominant trend in semantic theorizing about future contingents—paradigmatically, Thomason (1970) and MacFarlane himself (2003, 2014)—has maintained that the apparent tension between the “open future” and the “determinacy intuition” is in fact merely apparent. In short, such theorists seek to maintain both of the following two theses: (i) the open future: Future contingents are not true, and (ii) retro-closure: From the fact that something is true, it follows that it was the case that it would be true. It is well-known that reflection on the problem of future contingents has in many ways been inspired by importantly parallel issues regarding divine omniscience, indeterminism, and time. In this paper, we take up this perspective, and ask what accepting both the open future and retro-closure predicts about omniscience. When we theorize about a perfect knower, we are theorizing about what an agent ought, and ought not, to believe. Our contention is that there isn’t an acceptable view of ideally rational belief given the assumptions of the open future and retro-closure, and thus this casts doubt on the conjunction of those assumptions. (shrink)
Does rationality require logical omniscience? Our best formal theories of rationality imply that it does, but our ordinary evaluations of rationality seem to suggest otherwise. This paper aims to resolve the tension by arguing that our ordinary evaluations of rationality are not only consistent with the thesis that rationality requires logical omniscience, but also provide a compelling rationale for accepting this thesis in the first place. This paper also defends an account of apriori justification for logical beliefs that (...) is designed to explain the rational requirement of logical omniscience. On this account, apriori justification for beliefs about logic has its source in logical facts, rather than psychological facts about experience, reasoning, or understanding. This account has important consequences for the epistemic role of experience in the logical domain. In a slogan, the epistemic role of experience in the apriori domain is not a justifying role, but rather an enabling and disabling role. (shrink)
The main goal of this paper is to investigate what explanatory resources Robert Brandom’s distinction between acknowledged and consequential commitments affords in relation to the problem of logical omniscience. With this distinction the importance of the doxastic perspective under consideration for the relationship between logic and norms of reasoning is emphasized, and it becomes possible to handle a number of problematic cases discussed in the literature without thereby incurring a commitment to revisionism about logic. One such case in particular (...) is the preface paradox, which will receive an extensive treatment. As we shall see, the problem of logical omniscience not only arises within theories based on deductive logic; but also within the recent paradigm shift in psychology of reasoning. So dealing with this problem is important not only for philosophical purposes but also from a psychological perspective. (shrink)
In this paper, I investigate whether we can use a world-involving framework to model the epistemic states of non-ideal agents. The standard possible-world framework falters in this respect because of a commitment to logical omniscience. A familiar attempt to overcome this problem centers around the use of impossible worlds where the truths of logic can be false. As we shall see, if we admit impossible worlds where “anything goes” in modal space, it is easy to model extremely non-ideal agents (...) that are incapable of performing even the most elementary logical deductions. A much harder, and considerably less investigated challenge is to ensure that the resulting modal space can also be used to model moderately ideal agents that are not logically omniscient but nevertheless logically competent. Intuitively, while such agents may fail to rule out subtly impossible worlds that verify complex logical falsehoods, they are nevertheless able to rule out blatantly impossible worlds that verify obvious logical falsehoods. To model moderately ideal agents, I argue, the job is to construct a modal space that contains only possible and non-trivially impossible worlds where it is not the case that “anything goes”. But I prove that it is impossible to develop an impossible-world framework that can do this job and that satisfies certain standard conditions. Effectively, I show that attempts to model moderately ideal agents in a world-involving framework collapse to modeling either logical omniscient agents, or extremely non-ideal agents. (shrink)
I discuss three ways of responding to the logical omniscience problems faced by traditional ‘possible worlds’ epistemic logics. Two of these responses were put forward by Hintikka and the third by Cresswell; all three have been influential in the literature on epistemic logic. I show that both of Hintikka's responses fail and present some problems for Cresswell’s. Although Cresswell's approach can be amended to avoid certain unpalatable consequences, the resulting formal framework collapses to a sentential model of knowledge, which (...) defenders of the ‘possible worlds’ approach are frequently critical of. (shrink)
Epistemic logics based on the possible worlds semantics suffer from the problem of logical omniscience, whereby agents are described as knowing all logical consequences of what they know, including all tautologies. This problem is doubly challenging: on the one hand, agents should be treated as logically non-omniscient, and on the other hand, as moderately logically competent. Many responses to logical omniscience fail to meet this double challenge because the concepts of knowledge and reasoning are not properly separated. In (...) this paper, I present a dynamic logic of knowledge that models an agent’s epistemic state as it evolves over the course of reasoning. I show that the logic does not sacrifice logical competence on the altar of logical non- omniscience. (shrink)
It is said that faith in a divine agent is partly an attitude of trust; believers typically find assurance in the conception of a divine being's will, and cherish confidence in its capacity to implement its intentions and plans. Yet, there would be little point in trusting in the will of any being without assuming its ability to both act and know, and perhaps it is only by assuming divine omniscience that one can retain the confidence in the efficacy (...) and direction of divine agency that has long been the lure of certain religious traditions. (shrink)
The purpose of this paper is to consider the explanatory resources that Robert Brandom‟s distinction between acknowledged and consequential commitments affords in relation to the problem of logical omniscience. With this distinction the importance of the doxastic perspective under consideration for the relationship between logic and norms of reasoning is emphasized, and it becomes possible to handle a number of problematic cases discussed in the literature without thereby incurring a commitment to revisionism about logic. 12.
Patrick Grim has put forward a set theoretical argument purporting to prove that omniscience is an inconsistent concept and a model theoretical argument for the claim that we cannot even consistently define omniscience. The former relies on the fact that the class of all truths seems to be an inconsistent multiplicity (or a proper class, a class that is not a set); the latter is based on the difficulty of quantifying over classes that are not sets. We first (...) address the set theoretical argument and make explicit some ways in which it depends on mathematical Platonism. Then we sketch a non Platonistic account of inconsistent multiplicities, based on the notion of indefinite extensibility, and show how Grim’s set theoretical argument could fail to be conclusive in such a context. Finally, we confront Grim’s model theoretical argument suggesting a way to define a being as omniscient without quantifying over any inconsistent multiplicity. (shrink)
Patrick Grim and Einar Duenger Bohn have recently argued that there can be no perfectly knowing Being. In particular, they urge that the object of omniscience is logically absurd or requires an impossible maximal point of all knowledge. I argue that, given a more classical notion of omniscience found in Aquinas and Augustine, we can shift the focus of perfect knowledge from what that being must know to the mode of that being’s understanding. Since Grim and Bohn focus (...) on the object rather than mode of God’s knowledge, this classical approach to omniscience undermines their objections. (shrink)
A very weak omniscience principle is formulated, related omniscience principlesare considered, and the theorem that a function of bounded variation is the difference of two increasing functions is shown to be equivalent to the omniscience principle WLPO. It is a so shown that an arbitrary function with located variation on an interval is the difference of two increasing functions.
I contend that William Hasker’s argument to show omniscience incompatible with human freedom trades on an ambiguity between altering and bringing about the past, and that it is the latter only which is invoked by one who thinks they are compatible. I then use his notion of precluding circumstances to suggest that what gives the appearance of our inability to freely bring about the future (and hence that omniscience is incompatible with freedom) is that, from God’s perspective of (...) foreknowledge, it is as if the event has already occurred, but that as if conditions do not tell us about the conditions under which the act was performed (whether it was free or not). (shrink)
I argue that if deliberation is incompatible with (fore)knowing what one is going to do at the time of the deliberation, then God cannot deliberate. However, this thesis cannot be used to show either that God cannot act intentionally or that human persons cannot deliberate. Further, I have suggested that though omniscience is incompatible with deliberation, it is not incompatible with either some speculation or knowing something on the grounds of inference.
Recently Patrick Grim and Einar Duenger Bohn have argued that there can be no perfectly knowing Being. In particular, they urge that the object of omniscience is logically absurd (Grim) or requires an impossible maximal point of all knowledge (Bohn). I argue that, given a more classical notion of omniscience found in Aquinas and Augustine, we can shift the focus of perfect knowledge from what that being must know to the mode of that being’s understanding. Since Grim and (...) Bohn focus on the object rather than mode of God’s knowledge, this classical approach to omniscience undermines their objections. (shrink)
Recently, several philosophers have moved from a classical account of divine omniscience according to which God knows all truths to a restricted account of divine omniscience according to which God knows all knowable truths. But an important objection offered by Alexander Pruss threatens to show that if God knows all knowable truths, God must also know all truths. In this paper, I show that there is a way out of Pruss’s objection for the advocate of restricted omniscience (...) if she will define her view in terms of ways of knowing rather than in terms of logical possibilities. (shrink)
Several theorists (Merricks, Westphal, and McCall) have recently claimed to offer a novel way to respond to the dilemma of freedom and foreknowledge, rooted in Molina's insight that God's beliefs depend on what we do, rather than the other way around. In this paper we argue that these responses either beg the question, or else are dressed-up versions of Ockhamism.
This paper argues against the sufficiency of Alvin Plantinga’s free will defense, as presented in God, freedom, and evil as a response to the logical problem of evil. I begin by introducing the fundamental issues present in the problem of evil and proceed to present Plantinga’s response. Next, I argue that, despite the argument’s wide acceptance in the field, a central notion to the defense, transworld depravity, is internally inconsistent and that attempts to resolve the problem would result in an (...) abandonment of the original terms of the discussion. Finally, I consider some potential alternatives for a free will defense beyond the one presented by Plantinga and conclude that the logical problem of evil may have more worth as a philosophical topic than has been thought in recent years. (shrink)
Given anti-individualism, a subject might have a priori (non-empirical)knowledge that she herself is thinking that p, have complete and exhaustive explicational knowledge of all of the concepts composing the content that p, and yet still need empirical information (e.g. regarding her embedding conditions and history) prior to being in a position to apply her exhaustive conceptual knowledge in a knowledgeable way to the thought that p. This result should be welcomed by anti-individualists: it squares with everything that compatibilist-minded anti-individualists have (...) said regarding e.g. the compatibility of anti-individualism and basic self-knowledge; and more importantly it contains the crux of a response to McKinsey-style arguments against anti-individualism. (shrink)
I discuss the propositional knowledge of an omniscient being, knowledge of facts that can be represented by that-clauses in sentences such as ‘John knows that the world is round.’ I shall focus upon questions about a supposedly omniscient being who propositionally knows the truth about all current states of affairs. I shall argue that there is no such being.
At first glance, the properties being omniscient and being worthy of worship might appear to be perfectly co-instantiable. But there are reasons to be worried about this co-instantiability, as it turns out that, depending on our commitments with respect to certain kinds of knowledge and notions of personhood, it might be the case that no being—God included—could instantiate both. In this paper, I lay out and motivate this claim before going on to consider a variety of responses—some more plausible than (...) others—that may be offered by the theist. (shrink)
In Atheism: A Philosophical Justification, Michael Martin argues that to posit a God that is both omnipotent and omniscient is philosophically incoherent. I challenge this argument by proposing that a God who is necessarily omniscient is more powerful than a God who is contingently omniscient. I then argue that being omnipotent entails being omniscient by showing that for an all-powerful being to be all-powerful in any meaningful way, it must possess complete knowledge about all states of affairs and thus must (...) be understood to be omniscient. (shrink)
In this paper we study a reducibility that has been introduced by Klaus Weihrauch or, more precisely, a natural extension for multi-valued functions on represented spaces. We call the corresponding equivalence classes Weihrauch degrees and we show that the corresponding partial order induces a lower semi-lattice. It turns out that parallelization is a closure operator for this semi-lattice and that the parallelized Weihrauch degrees even form a lattice into which the Medvedev lattice and the Turing degrees can be embedded. The (...) importance of Weihrauch degrees is based on the fact that multi-valued functions on represented spaces can be considered as realizers of mathematical theorems in a very natural way and studying the Weihrauch reductions between theorems in this sense means to ask which theorems can be transformed continuously or computably into each other. As crucial corner points of this classification scheme the limited principle of omniscience LPO, the lesser limited principle of omniscience LLPO and their parallelizations are studied. It is proved that parallelized LLPO is equivalent to Weak Kőnig's Lemma and hence to the Hahn—Banach Theorem in this new and very strong sense. We call a multi-valued function weakly computable if it is reducible to the Weihrauch degree of parallelized LLPO and we present a new proof, based on a computational version of Kleene's ternary logic, that the class of weakly computable operations is closed under composition. Moreover, weakly computable operations on computable metric spaces are characterized as operations that admit upper semi-computable compact-valued selectors and it is proved that any single-valued weakly computable operation is already computable in the ordinary sense. (shrink)
In recent years the question of whether adding the limited principle of omniscience, LPO, to constructive Zermelo–Fraenkel set theory, CZF, increases its strength has arisen several times. As the addition of excluded middle for atomic formulae to CZF results in a rather strong theory, i.e. much stronger than classical Zermelo set theory, it is not obvious that its augmentation by LPO would be proof-theoretically benign. The purpose of this paper is to show that CZF+RDC+LPO has indeed the same strength (...) as CZF, where RDC stands for relativized dependent choice. In particular, these theories prove the same Π02 theorems of arithmetic. (shrink)
I’m going to argue that omniscience is impossible and therefore that there is no God. The argument turns on the notion of grounding. After illustrating and clarifying that notion, I’ll start the argument in earnest. The first step will be to lay out five claims, one of which is the claim that there is an omniscient being, and the other four of which are claims about grounding. I’ll prove that these five claims are jointly inconsistent. Then I’ll argue for (...) the truth of each of them except the claim that there is an omniscient being. From these arguments it follows that there are no omniscient beings and thus that there is no God. (shrink)
Brian Garrett (Analysis (2012), 293–5) comments on McCall's paper (Analysis (2011), 501–6). McCall had claimed that since the truth of true empirical propositions supervenes on, and depends upon, empirical fact, what God knows and does not know also depends upon being, i.e. upon facts. Consequently God's foreknowing what I freely decide to do depends upon what I freely do. Garrett objects that the dependence of truth on being seems to play no essential role in McCall's argument. McCall replies that his (...) argument is an up-to-date version of Luis de Molina's 16th century reconciliation of freewill with omniscience, in which the dependence of God's knowledge on what humans do is crucial. (shrink)
This essay examines a conflict between God's omnipotence and His omniscience. I discuss our intuitions regarding omnipotence and omniscience and describe a method by which we can decide whether a being is omnipotent. I consider the most promising versions of omnipotence and argue that they produce a genuine conflict with omniscience. Finally, I suggest that we can take the example of omniscience and generalize it to several of God's essential properties and thereby reveal incompatibilities that result (...) even from sophisticated conceptions of divine attributes. (Published Online August 11 2004). (shrink)
We propose a model for belief which is free of presuppositions. Current models for belief suffer from two difficulties. One is the well known problem of logical omniscience which tends to follow from most models. But a more important one is the fact that most models do not even attempt to answer the question what it means for someone to believe something, and just what it is that is believed. We provide a flexible model which allows us to give (...) meaning to beliefs in general contexts, including the context of animal belief , and of human belief which is expressed in language. (shrink)
In a recent paper, Dennis Whitcomb argues that omniscience is impossible. But if there cannot be any omniscient beings, then God, at least as traditionally conceived, does not exist. The objection is, roughly, that the thesis that there is an omniscient being, in conjunction with some principles about grounding, such as its transitivity and irreflexivity, entails a contradiction. Since each of these principles is highly plausible, divine omniscience has to go. In this article, I argue that Whitcomb's argument, (...) if sound, has several unacceptable consequences. Among others, it implies that nobody knows that someone has knowledge, that, for most of us, all of our beliefs are false, and that there are no truths. This reductio all by itself provides sufficient reason to reject the argument. However, I also provide a diagnosis of where precisely the argument goes wrong. I argue that Whitcomb's crucial notion of grounding actually covers two distinct relations and that the principle of transitivity is true only for cases in which one of these relations holds rather than both of them. (shrink)
Some, notably Peter van Inwagen, in order to avoid problems with free will and omniscience, replace the condition that an omniscient being knows all true propositions with a version of the apparently weaker condition that an omniscient being knows all knowable true propositions. I shall show that the apparently weaker condition, when conjoined with uncontroversial claims and the logical closure of an omniscient being's knowledge, still yields the claim that an omniscient being knows all true propositions.
In contemporary philosophy of religion, the doctrine of omniscience is typically rendered propositionally, as the claim that God knows all true propositions (and believes none that are false). But feminist work makes clear what even the analytic tradition sometimes confesses, namely, that propositional knowledge is quite limited in scope. The adequacy of propositional conceptions of omniscience is therefore in question. This paper draws on the work of feminist epistemologists to articulate alternative renderings of omniscience which remedy the (...) deficiencies of the traditional formulation. (shrink)
Patrick Grim argues that God cannot beomniscient because no one other than me canacquire knowledge de se of myself. Inparticular, according to Grim, God cannot knowwhat I know in knowing that I am making amess. I argue, however, that given twoplausible principles regarding divineattributes there is no reason to accept Grim'sconclusion that God cannot be omniscient. Inthis paper I focus on the relationship betweendivine omniscience and necessaryimpossibilities, in contrast to the generaltrend of research since Aquinas, which hasconcentrated on the (...) relationship between divineomnipotence and necessary impossibilities. (shrink)
Omniscience is the divine attribute of possessing complete or unlimited knowledge. This article examines motivations for taking such a property to be a divine attribute, attempts to define or analyse omniscience, possible limitations on the extent of divine knowledge, and, finally, objections either to the coherence of the concept or to its compatibility with other divine attributes or with widely accepted claims.
The cause of an event must continue over a period at which the effect is not occurring and the whole period at which it is occurring. It follows that simultaneous causation and backward causation are metaphysically impossible. I distinguish among events said to occur at a time, ‘hard’ events which really occur solely at that time and ‘soft’ events which occur partly at another time. God’s beliefs at a time are hard events at that time. It follows that if God (...) is a temporal being, he cannot know infallibly what either we or he will do freely at a future time; and if God is timeless, he cannot know what happens in time. Hence we must define God’s ‘omniscience’ in such a way as to exclude any knowledge of future free actions. I discuss in an Appendix how far this view is compatible with Scripture and Church tradition. (shrink)
This paper argues that there is a conflict between divine omniscience and the human right to privacy. The right to privacy derives from the right to moral autonomy, which human persons possess even against a divine being. It follows that if God exists and persists in knowing all things, his knowledge is a non-justifiable violation of a human right. On the other hand, if God exists and restricts his knowing in deference to human privacy, it follows that he cannot (...) fulfill the traditional function of being the perfect and final judge of all things. (shrink)
In ‘Omniprescient Agency’ David P. Hunt challenges an argument against the possibility of an omniscient agent. The argument – my own in ‘Agency and Omniscience’ – assumes that an agent is a being capable of intentional action, where, minimally, an action is intentional only if it is caused, in part, by the agent's intending. The latter, I claimed, is governed by a psychological principle of ‘least effort’, namely, that no one intends without antecedently feeling that deliberate effort is needed (...) to achieve desired goals, such effort has a chance of success, and it is yet contingent whether the effort will be expended and the goals realized. The goals can be anything from immediate intentional doings, tryings or basic actions, to remote and perhaps unlikely consequences of actions, e.g. global justice. The thrust of the principle is that it would be impossible for a wholly rational self-aware agent to intend without a background presumption of an open future as concerns the desired state and the means to it. But this presumption embodies a sense of contingency which, in turn, requires an acknowledged ignorance about what the future holds, otherwise the future would appear closed relative to present knowledge with the desired state presented as either guaranteed or ruled out . Regardless whether this self-directed attitude is accurate, it follows that intentional action precludes complete knowledge of one's present and future. Consequently, no omniscient or omniprescient being can be an agent. (shrink)
A difficulty for a view of divine eternity as timelessness is that if time is tensed, then God, in virtue of His omniscience, must know tensed facts. But tensed facts, such as It is now t, can only be known by a temporally located being.Defenders of divine atemporality may attempt to escape the force of this argument by contending either that a timeless being can know tensed facts or else that ignorance of tensed facts is compatible with divine (...) class='Hi'>omniscience. Kvanvig, Wierenga, and Leftow adopt both of these strategies in their various defenses of divine timelessness. Their respective solutions are analyzed in detail and shown to be untenable.Thus, if the theist holds to a tensed view of time, he should construe divine eternity in terms of omnitemporality. (shrink)
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. (shrink)
A certain objection to belief in God is based on the intrinsic incoherence of the concept of Divine Being or God. In particular, it questions the major traditional characteristic, notably omniscience, and its relation to omnipotence, moral unassailability, and absence of embodiment on the part of the Divine Being. In this paper, an attempt is made to counter this objection by an appeal, not to natural theology, but rather to physicalism in its application to human beings, and by extension (...) to the possible consistency of God’s omniscience with the other divine attributes, which philosophers such as Michael Martin have found to be mutually inconsistent and therefore wanting. (shrink)
There is a familiar argument based on the principle that the past is fixed that, if God foreknows what I will do, I do not have the power to act otherwise. So, there is a problem about reconciling divine omniscience with the power to do otherwise. However the problem posed by the argument does not provide a good reason for adopting the view that God is outside time. In particular, arguments for the fixity of the past, if successful, either (...) establish His timelessness independently of the problem, or mean that the problem could not be solved by adopting the view that He is timeless. (Published Online April 7 2006). (shrink)
(1993). Managing the future: Science, the Humanities, and the myth of omniscience. World Futures: Vol. 38, Theoretical Achievements and Practical Applications of General Evolutionary Theory, pp. 157-164.
In "Omniprescient Agency" (Religious Studies 28, 1992) David P. Hunt challenges an argument against the possibility of an omniscient agent. The argument—my own in "Agency and Omniscience" (Religious Studies 27, 1991)—assumes that an agent is a being capable of intentional action, where, minimally, an action is intentional only if it is caused, in part, by the agent's intending. The latter, I claimed, is governed by a psychological principle of "least effort," viz., that no one intends without antecedently feeling that (...) (i) deliberate effort is needed to achieve desired goals, (ii) such effort has a chance of success, and (iii) it is yet contingent whether the effort will be expended and the goals realized. The goals can be anything from immediate intentional doings, tryings or basic actions, to remote and perhaps unlikely consequences of actions, e.g., global justice. The thrust of the principle is that it would be impossible for a wholly rational self-aware agent to intend without a background presumption of an open future as concerns the desired state and the means to it. But this presumption embodies a sense of contingency which, in turn, requires an acknowledged ignorance about what the future holds, otherwise the future would appear closed relative to present knowledge with the desired state presented as either guaranteed (necessary) or ruled out (impossible). Regardless whether this self-directed attitude is accurate, it follows that intentional action precludes complete knowledge of one's present and future. Consequently, no omniscient or omniprescient being can be an agent. (shrink)
IN COMPARISON with other doctrines Cthe doctrine of omnipotence, for example Cthe proper formulation of the doctrine of omniscience has not seemed especially problematic. Once we accept the contemporary wisdom that knowledge is knowledge of truths, the formulation of the traditional doctrine seems straightforward: to be omniscient is just to know all truths. What has seemed problematic, rather, is whether the doctrine is itself true. In particular, many have wondered whether anyone can know the parts of the future not (...) necessitated in any way by the present or past. (shrink)
Suppose there are possible worlds in which God exists but Anselm does not. Then (I argue) there are possible worlds in which Anselm does not exist, but God cannot even entertain the thought that he does not. In such worlds Anselm does not exist, but God does not know that. This, I argue, is incompatible with (a straightforward construal of) the doctrine of God's essential omniscience. Considerations involving negative existentials also call into question a certain picture of creation, on (...) which God chooses which particular (possible) individuals to create. They suggest that there is an element of brute contingency about which individuals exist. (shrink)