Online research in philosophy

Naive deductive accounts of confirmation have the undesirable consequence that if E confirms H, then E also confirms the conjunction H & X, for any X—even if X is utterly irrelevant to H (and E). Bayesian accounts of confirmation also have this property (in the case of deductive evidence). Several Bayesians have attempted to soften the impact of this fact by arguing that—according to Bayesian accounts of confirmation— E will confirm the conjunction H & X less strongly than E confirms H (again, in the case of deductive evidence). I argue that existing Bayesian “resolutions” of this problem are inadequate in several important respects. In the end, I suggest a new‐and‐improved Bayesian account (and understanding) of the problem of irrelevant conjunction.

Recent discussion of the problem of evil has centered around what is known as the probabilistic or evidential argument from evil. According to this argument the evil in our world is evidence against the existence of God, even though evil is logically consistent with God’s existing. Based on this it is claimed it is irrational to believe one of the traditional theistic religions, unless there is overwhelming positive evidence to counter this negative evidence. One of the most important and widely discussed versions of this argument is due to Paul Draper.1 In this paper I will look at Draper’s argument and argue that he has made a simple fundamental error; as a result his argument is irrelevant to most theists. After discussing this error in Draper’s argument, I will discuss probabilistic arguments from evil from the perspective of confirmation theory. The error in Draper’s argument is easily made and could occur in any probabilistic argument from evil; looking at confirmation theory and probabilistic arguments from evil will provide insight into reasoning about evil and belief in God.

I argue that the knowledge argument is best understood as an argument for the existence of non-physical properties of material objects, or colours. I suggest that the knowledge argument is standardly presented as an argument for the existence of qualia because it is implicitly assumed that physics “tell us” that what it is like to perceive colour is determined, not by properties of material objects, but by properties of perceiving subjects; hence any gaps in Mary’s knowledge must be gaps in her knowledge about perceiving subjects. If nothing else, this physicalist assumption is odd given that the knowledge argument is supposed to be an argument against physicalism. Using the knowledge argument as an argument for the existence of non-physical colours is consistent with the transparency of perceptual experience. Moreover, rejecting the physicalist assumption behind the orthodox interpretation of the knowledge argument undermines the motivation for thinking of non-physical colours as epiphenomenal.

This paper critically analyzes Sherrilyn Roush’s (Tracking truth: knowledge, evidence and science, 2005) definition of evidence and especially her powerful defence that in the ideal, a claim should be probable to be evidence for anything. We suggest that Roush treats not one sense of ‘evidence’ but three: relevance, leveraging and grounds for knowledge; and that different parts of her argument fare differently with respect to different senses. For relevance, we argue that probable evidence is sufficient but not necessary for Roush’s own two criteria of evidence to be met. With respect to grounds for knowledge, we agree that high probability evidence is indeed ideal for the central reason Roush gives: When believing a hypothesis on the basis of e it is desirable that e be probable. But we maintain that her further argument that Bayesians need probable evidence to warrant the method they recommend for belief revision rests on a mistaken interpretation of Bayesian conditionalization. Moreover, we argue that attempts to reconcile Roush’s arguments with Bayesianism fail. For leveraging, which we agree is a matter of great importance, the requirement that evidence be probable suffices for leveraging to the probability of the hypothesis if either one of Roush’s two criteria for evidence are met. Insisting on both then seems excessive. To finish, we show how evidence, as Roush defines it, can fail to track the hypothesis. This can remedied by adding a requirement that evidence be probable, suggesting another rationale for taking probable evidence as ideal—but only for a grounds-for-knowledge sense of evidence.

The fundamental constants that are involved in the laws of physics which describe our universe are finely tuned for life, in the sense that if some of the constants had slightly different values life could not exist. Some people hold that this provides evidence for the existence of God. I will present a probabilistic version of this fine-tuning argument which is stronger than all other versions in the literature. Nevertheless, I will show that one can have reasonable opinions such that the fine-tuning argument doesn't lead to an increase in one's probability for the existence of God. The fine-tuning argument Objective versus subjective probability Observational selection effects The problem of old evidence Against the fine-tuning argument Many universes.

The Carter-Leslie Doomsday argument, as standardly presented, relies on the assumption that you have knowledge of your approximate birth rank. I demonstrate that the Doomsday argument can still be given in a situation where you have no knowledge of your birth rank. This allows one to reply to Bostrom's defense of the Doomsday argument against the refutation based on the idea that your existence makes it more likely that many observers exist.

I argue that the standard way of formalizing the fine-tuning argument for design is flawed, and I present an alternative formalization. On the alternative formalization, the existence of life is not treated as the evidence that confirms design; instead it is treated as part of the background knowledge, while the fact that fine tuning is required for life serves as the evidence. I argue that the alternative better captures the informal line of thought that gives the fine-tuning argument its intuitive plausibility, and I show that the alternative formalization avoids all of the most prominent objections to the fine-tuning argument, including the objection from observation selection effects, the problem of old evidence, the problem of non-normalizable probability measures and a further objection due to Monton. I conclude that the alternative formalization is the one that attention should be focused on.

The Fine-Tuning Argument (FTA) is a variant of the Design Argument for the existence of God. In this paper the evidence of fine-tuning is explained and the Fine-Tuning Design Argument for God is presented. Then two objections are covered. The first objection is that fine-tuning can be explained in terms of the existence of multiple universes (the 'multiverse') plus the operation of the anthropic principle. The second objection is the 'normalizability problem'– the objection that the Fine-Tuning Argument fails because fine-tuning is not actually improbable.

Bayesian epistemology postulates a probabilistic analysis of many sorts of ordinary and scientific reasoning. Huber ([2005]) has provided a novel criticism of Bayesianism, whose core argument involves a challenging issue: confirmation by uncertain evidence. In this paper, we argue that under a properly defined Bayesian account of confirmation by uncertain evidence, Huber's criticism fails. By contrast, our discussion will highlight what we take as some new and appealing features of Bayesian confirmation theory. Introduction Uncertain Evidence and Bayesian Confirmation Bayesian Confirmation by Uncertain Evidence: Test Cases and Basic Principles CiteULike Connotea Del.icio.us What's this?

In this paper, we discuss three probabilistic arguments for the existence of multiple universes. First, we provide an analysis of total evidence and use that analysis to defend Roger White's "this universe" objection to a standard fine-tuning argument for multiple universes. Second, we explain why Rodney Holder's recent cosmological argument for multiple universes is unconvincing. Third, we develop a "Cartesian argument" for multiple universes. While this argument is not open to the objections previously noted, we show that, given certain highly plausible assumptions about evidence and epistemic probability, the proposition which it treats as evidence cannot coherently be regarded as evidence for anything. This raises the question of whether to reject the assumptions or accept that such a proposition cannot be evidence.