Substantially re-written and updated, this edition of 'The Existence of God' presents arguments such as the existence of the laws of nature, 'fine-tuning' of the universe, moral awareness and evidence of miracles, to prove the case that there is a God.

Jeremy Gwiazda has criticized my claim that God, understood as an omnipotent, omniscient, and perfectly free person is a person ’of the simplest possible kind’ on the grounds that omnipotence, etc., as spelled out by me are omnipotence, etc., of restricted kinds, and so less simple forms of these properties than maximal forms would be. However, the account which I gave of these properties in ’The Christian God’ (although not in ’The Coherence of Theism’) shows that, when they are defined (...) in certain ways, they all follow from one property of ’pure, limitless, intentional power’. I argue here that a person who has these properties so defined is a person ’of the simplest possible kind’. (shrink)

Jeremy Gwiazda has criticized my claim that God, understood as an omnipotent, omniscient, and perfectly free person is a person ‘of the simplest possible kind’ on the grounds that omnipotence etc. as spelled out by me are omnipotence etc. of restricted kinds, and so less simple forms of these properties than maximal forms would be. However the account which I gave of these properties in The Christian God shows that, when they are defined in certain ways, they all follow from (...) one property of ‘pure, limitless, intentional power’. I argue here that a person who has these properties so defined is a person ‘of the simplest possible kind’. (shrink)

Scientists often appeal to a criterion of simplicity as a consideration that helps them decide which hypotheses are most plausible. Some such principle seems to be essential; the data, all by themselves, apparently cannot single out as best one hypothesis among the set of competitors.

The epistemic probability of A given B is the degree to which B evidentially supports A, or makes A plausible. This paper is a first step in answering the question of what determines the values of epistemic probabilities. I break this question into two parts: the structural question and the substantive question. Just as an object’s weight is determined by its mass and gravitational acceleration, some probabilities are determined by other, more basic ones. The structural question asks what probabilities are (...) not determined in this way—these are the basic probabilities which determine values for all other probabilities. The substantive question asks how the values of these basic probabilities are determined. I defend an answer to the structural question on which basic probabilities are the probabilities of atomic propositions conditional on potential direct explanations. I defend this against the view, implicit in orthodox mathematical treatments of probability, that basic probabilities are the unconditional probabilities of complete worlds. I then apply my answer to the structural question to clear up common confusions in expositions of Bayesianism and shed light on the “problem of the priors.”. (shrink)

Raphael Lataster and Herman Philipse present an argument which they think decisively demonstrates polytheism over monotheism, if theism is assumed. Far from being decisive, the argument depends on very controversial and likely false assumptions about how to treat infinities in probability. Moreover, these problems are well known. Here, we focus on three objections. First, the authors rely on both countable additivity and the Principle of Indifference, which contradict each other. Second, the authors rely on a particular way of dividing up (...) the possibility space, when there are equally as reasonable alternative divisions which give different answers to the one the authors arrived at. Third, the authors’ argument proves too much, giving us an argument against many positions we should not be able to argue against so easily. (shrink)

This article sets out a formal procedure for determining the probability that God would do a specified action, using our moral knowledge and understanding God as a perfect being. To motivate developing the procedure I show how natural theology – design arguments, the problems of evil and divine hiddenness, and the treatment of miracles and religious experiences as evidence for claims about God – routinely appeals to judgments involving these probabilities. To set out the procedure, I describe a decision-theoretic model (...) for practical reasoning which is deontological so as to appeal to theists, but is designed not to presuppose any substantive moral commitments, and to accommodate normative and non-normative uncertainty. Then I explain how judgments about what we probably ought to do can be transformed into judgments about what God would probably do. Then I show the usefulness of the procedure by describing how it can help structure discussions in natural theology and a-theology, and how it offers an attractive alternative to ‘skeptical theism’. (shrink)

In this paper, I motivate the view that quantitative parsimony is a theoretical virtue: that is, we should be concerned not only to minimize the number of kinds of entities postulated by our theories (i. e. maximize qualitative parsimony), but we should also minimize the number of entities postulated which fall under those kinds. In order to motivate this view, I consider two cases from the history of science: the postulation of the neutrino and the proposal of Avogadro's hypothesis. I (...) also consider two issues concerning how a principle of quantitative parsimony should be framed. (shrink)

Theistic and analytic philosophers of religion typically privilege classical theism and monotheism by ignoring or underestimating the great threat of polytheism. We develop an argument from infinitely many alternatives, which decisively demonstrates that if a monotheistic or polytheistic god-model obtains, it will almost certainly be polytheistic. Probabilistic calculations are performed in order to illustrate the difficulties faced by the monotheistic proponent. After considering possible objections, such as whether there should be limits placed on how many possible god-models could obtain, we (...) conclude that our argument from infinitely many alternatives is sound, and highly unlikely to be overcome. (shrink)

This chapter contains sections titled: Introduction Goal and Scope of the Argument The Concept of a Miracle Textual Assumptions Background Facts: Death and Burial The Salient Facts: W, D, and P Probabilistic Cumulative Case Arguments: Nature and Structure The Testimony of the Women: Bayes Factor Analysis The Testimony of the Disciples: Bayes Factor Analysis The Conversion of Paul: Bayes Factor Analysis The Collective Force of the Salient Facts Independence Hume's Maxim and Worldview Worries Plantinga's Principle of Dwindling Probabilities Knavery, Folly, (...) and the Love of Wonder Conclusion References. (shrink)

Four important arguments for probabilism—the Dutch Book, representation theorem, calibration, and gradational accuracy arguments—have a strikingly similar structure. Each begins with a mathematical theorem, a conditional with an existentially quantified consequent, of the general form: if your credences are not probabilities, then there is a way in which your rationality is impugned. Each argument concludes that rationality requires your credences to be probabilities. I contend that each argument is invalid as formulated. In each case there is a mirror-image theorem and (...) a corresponding argument of exactly equal strength that concludes that rationality requires your credences not to be probabilities. Some further consideration is needed to break this symmetry in favour of probabilism. (shrink)

Parsimony is a virtue of empirical theories. Is it also a virtue of philosophical theories? I review four contemporary accounts of the virtue of parsimony in empirical theorizing, and consider how each might apply to two prominent appeals to parsimony in the philosophical literature, those made on behalf of physicalism and on behalf of nominalism. None of the accounts of the virtue of parsimony extends naturally to either of these philosophical cases. This suggests that in typical philosophical contexts, ontological simplicity (...) has no evidential value. (shrink)

A central problem facing a probabilistic approach to the problem of induction is the difficulty of sufficiently constraining prior probabilities so as to yield the conclusion that induction is cogent. The Principle of Indifference, according to which alternatives are equiprobable when one has no grounds for preferring one over another, represents one way of addressing this problem; however, the Principle faces the well-known problem that multiple interpretations of it are possible, leading to incompatible conclusions. I propose a partial solution to (...) the latter problem, drawing on the notion of explanatory priority. The resulting synthesis of Bayesian and inference-to-best-explanation approaches affords a principled defense of prior probability distributions that support induction. (shrink)

Four important arguments for probabilism—the Dutch Book, representation theorem, calibration, and gradational accuracy arguments—have a strikingly similar structure. Each begins with a mathematical theorem, a conditional with an existentially quantified consequent, of the general form: if your credences are not probabilities, then there is a way in which your rationality is impugned.Each argument concludes that rationality requires your credences to be probabilities.I contend that each argument is invalid as formulated. In each case there is a mirror-image theorem and a corresponding (...) argument of exactly equal strength that concludes that rationality requires your credences not to be probabilities. Some further consideration is needed to break this symmetry in favour of probabilism. I discuss the extent to which the original arguments can be buttressed.1. Introduction2. The Dutch Book Argument2.1. Saving the Dutch Book argument2.2. ‘The Dutch Book argument merely dramatizes an inconsistency in the attitudes of an agent whose credences violate probability theory’3. Representation Theorem-based Arguments4. The Calibration Argument5. The Gradational Accuracy Argument6. Conclusion. (shrink)

In this article, we examine in detail the New Atheists' most serious argument for the conclusion that God does not exist, namely, Richard Dawkins's Ultimate 747 Gambit. Dawkins relies upon a strong explanatory principle involving simplicity. We systematically inspect the various kinds of simplicity that Dawkins may invoke. Finding his crucial premises false on any common conception of simplicity, we conclude that Dawkins has not given good reason to think God does not exist.

In ’The Coherence of Theism’ Richard Swinburne writes that a person cannot be omniscient and perfectly free. In ’The Existence of God’ Swinburne writes that God is a person who is omniscient and perfectly free. There is a straightforward reason why the two passages are not in tension, but recognition of this reason raises a problem for Swinburne’s argument in ’The Existence of God’ (the conclusion of which is that God likely exists). In this paper I present the problem for (...) Swinburne’s argument. I then consider two potential responses and suggest that neither succeeds. (shrink)

Do the evils in the world make it unlikely that God exists? In the first half of this chapter, Paul Draper formulates a Humean argument from evil for an affirmative answer to this question. He compares the theistic hypothesis that an omnipotent, omniscient, and perfectly good God exists to a competing hypothesis called naturalism. He claims both that naturalism is simpler than theism, and that naturalism fits or “predicts” a variety of facts about good and evil much better than theism (...) does. After sketching a defense of these two claims, he briefly discusses several theistic responses to his argument. In the second half of the chapter, Trent Dougherty raises several important objections to Draper's argument. (shrink)

Defenders of Inference to the Best Explanation claim that explanatory factors should play an important role in empirical inference. They disagree, however, about how exactly to formulate this role. In particular, they disagree about whether to formulate IBE as an inference rule for full beliefs or for degrees of belief, as well as how a rule for degrees of belief should relate to Bayesianism. In this essay I advance a new argument against non-Bayesian versions of IBE. My argument focuses on (...) cases in which we are concerned with multiple levels of explanation of some phenomenon. I show that in many such cases, following IBE as an inference rule for full beliefs leads to deductively inconsistent beliefs, and following IBE as a non-Bayesian updating rule for degrees of belief leads to probabilistically incoherent degrees of belief. (shrink)

Parsimony arguments are advanced in both science and philosophy. How are they related? This question is a test case for Naturalismp, which is the thesis that philosophical theories and scientific theories should be evaluated by the same criteria. In this paper, I describe the justifications that attach to two types of parsimony argument in science. In the first, parsimony is a surrogate for likelihood. In the second, parsimony is relevant to estimating how accurately a model will predict new data when (...) fitted to old. I then consider how these two justifications apply to parsimony arguments in philosophy concerning theism and atheism, the mind/body problem, ethical realism, the question of whether mental properties are causally efficacious, and nominalism versus Platonism about numbers. (shrink)