This paper is about guessing: how people respond to a question when they aren’t certain of the answer. Guesses show surprising and systematic patterns that the most obvious theories don’t explain. We argue that these patterns reveal that people aim to optimize a tradeoff between accuracy and informativity when forming their guess. After spelling out our theory, we use it to argue that guessing plays a central role in our cognitive lives. In particular, our account of guessing yields new theories (...) of belief, assertion, and the conjunction fallacy—the psychological finding that people sometimes rank a conjunction as more probable than one of its conjuncts. More generally, we suggest that guessing helps explain how boundedly rational agents like us navigate a complex, uncertain world. (shrink)

I lay out the framework for my theory of sensory imagination in “Imagining as a guide to possibility.” Sensory imagining involves mental imagery , and crucially, in describing the content of imagining, I distinguish between qualitative content and assigned content. Qualitative content derives from the mental image itself; for visual imaginings, it is what is “pictured.” For example, visually imagine the Philadelphia Eagles defeating the Pittsburgh Steelers to win their first Super Bowl. You picture the greenness of the field and (...) the football’s brown oblong shape. Some of what you imagine isn’t explicitly pictured, however. That it is Sunday, that it is the Super Bowl: these facts are assigned. (shrink)

Recent attempts to resolve the Paradox of the Gatecrasher rest on a now familiar distinction between individual and bare statistical evidence. This paper investigates two such approaches, the causal approach to individual evidence and a recently influential (and award-winning) modal account that explicates individual evidence in terms of Nozick's notion of sensitivity. This paper offers counterexamples to both approaches, explicates a problem concerning necessary truths for the sensitivity account, and argues that either view is implausibly committed to the impossibility of (...) no-fault wrongful convictions. The paper finally concludes that the distinction between individual and bare statistical evidence cannot be maintained in terms of causation or sensitivity. We have to look elsewhere for a solution of the Paradox of the Gatecrasher. (shrink)

It has been argued that an advantage of the safety account over the sensitivity account is that the safety account preserves epistemic closure, while the sensitivity account implies epistemic closure failure. However, the argument fails to take the method-relativity of the modal conditions on knowledge, viz., sensitivity and safety, into account. In this paper, I argue that the sensitivity account and the safety account are on a par with respect to epistemic closure once the method-relativity of the modal conditions is (...) taken into account. Therefore, epistemic closure is no longer an arbiter in the debate. (shrink)

A number of prominent epistemologists claim that the principle of sensitivity “play[s] a starring role in the solution to some important epistemological problems”. I argue that traditional sensitivity accounts fail to explain even the most basic data that are usually considered to constitute their primary motivation. To establish this result I develop Gettier and lottery cases involving necessary truths. Since beliefs in necessary truths are sensitive by default, the resulting cases give rise to a serious explanatory problem for the defenders (...) of sensitivity accounts. It is furthermore argued that attempts to modally strengthen traditional sensitivity accounts to avoid the problem must appeal to a notion of safety—the primary competitor of sensitivity in the literature. The paper concludes that the explanatory virtues of sensitivity accounts are largely illusory. In the framework of modal epistemology, it is safety rather than sensitivity that does the heavy explanatory lifting with respect to Gettier cases, lottery examples, and other pertinent cases. (shrink)

Sensitivity has sometimes been thought to be a highly epistemologically significant property, serving as a proxy for a kind of responsiveness to the facts that ensure that the truth of our beliefs isn’t just a lucky coincidence. But it's an imperfect proxy: there are various well-known cases in which sensitivity-based anti-luck conditions return the wrong verdicts. And as a result of these failures, contemporary theorists often dismiss such conditions out of hand. I show here, though, that a sensitivity-based understanding of (...) epistemic luck can be developed that respects what was attractive about sensitivity-based approaches in the first place but that's immune to these failures. (shrink)

According to the sensitivity account of knowledge, S knows that p only if S's belief in p is sensitive in the sense that S would not believe that p if p were false. It is widely accepted that the sensitivity condition should be relativized to belief-formation methods to avoid putative counterexamples. A remaining issue for the account is how belief-formation methods should be individuated. In this paper, I argue that while a coarse-grained individuation is still susceptible to counterexamples, a fine-grained (...) individuation makes the target belief trivially insensitive. Therefore, there is no principled way of individuating belief-formation methods that helps the sensitivity account to accommodate different cases. (shrink)

The mentioning of error-possibilities makes us less likely to ascribe knowledge. This paper offers a novel psychological account of this data. The account appeals to “subadditivity,” a well-known psychological tendency to judge possibilities as more likely when they are disjunctively described.

What epistemic defect needs to show up in a skeptical scenario if it is to effectively target some belief? According to the false belief account, the targeted belief must be false in the skeptical scenario. According to the competing ignorance account, the targeted belief must fall short of being knowledge in the skeptical scenario. This paper argues for two claims. The first is that, contrary to what is often assumed, the ignorance account is superior to the false belief account. The (...) second is that the ignorance account ultimately hobbles the skeptic. It does so for two reasons. First, when this account is joined with either a closure-based skeptical argument or a skeptical underdetermination argument, the best the skeptic can do is show that we don’t know that we know. And second, the ignorance account directly implies the maligned KK principle. (shrink)

Rationalism, my target, says that in order to have perceptual knowledge, such as that your hand is making a fist, you must “antecedently” (or “independently”) know that skeptical scenarios don’t obtain, such as the skeptical scenario that you are in the Matrix. I motivate the specific form of Rationalism shared by, among others, White (Philos Stud 131:525–557, 2006) and Wright (Proc Aristot Soc Suppl Vol 78:167–212, 2004), which credits us with warrant to believe (or “accept”, in Wright’s terms) that our (...) senses are reliably veridical, where that warrant is one we enjoy by default, that is, without relying on any evidence or engaging in any positive argument. The problem with this form of Rationalism is that, even if you have default knowledge that your senses are reliable, this is not adequate to rule out every kind of skeptical scenario. The problem is created by one-off skeptical scenarios, scenarios that involve a highly reliable perceiver who, by a pure fluke, has a one-off, non-veridical experience. I claim you cannot infer that your present perceptual experience is veridical just on the basis of knowledge of your general reliability. More generally, if you infer that the present F is G, just on the basis of your knowledge that most Fs are Gs, this is what I call statistical inference, and, as I argue, statistical inference by itself does not generate knowledge. I defend this view of statistical inference against objections, including the objection that radical skepticism about our ordinary inductive knowledge will follow unless statistical inference generates knowledge. (shrink)

An extended critical investigation of Plantinga's evolutionary argument against naturalism (EAAN). -/- I wrote this a couple of years ago as a way of thinking through the argument, but now lack the ambition to revise it into a paper. (It's too long to be a paper, too short and too narrowly focused on one person's argument to be a book.) Rather than let it age in private, I'm sharing it publicly for anyone interested in Plantinga's argument.

One interesting and potentially attractive feature of the sensitivity account of knowledge is that it not only preserves knowledge of ordinary propositions, but also concedes the skeptic's intuition that we do not know skeptical hypotheses do not obtain. This paper challenges the sensitivity‐based reply to the skeptic, advocated by Robert Nozick, among others. Sensitivity generates an implausibly bizarre result that although we do not know we are not brains in vats (because a belief to this effect is insensitive), a real (...) BIV who is in a much worse epistemic situation can sensitively believe that it is not in the good case. This result reveals a fundamental problem with the sensitivity conditional: its antecedent is not suitable for picking out possibilities that are relevant for our epistemic evaluation. I then offer a systematic explanation of why it is the safety account—the main competitor of sensitivity—that picks out a more suitable set of possibilities. A consequence of this comparison is that the safety account delivers an overall more satisfying reply to the skeptic than sensitivity does. (shrink)

Outside the philosophy classroom, global skeptics – skeptics about all (purported) knowledge of the external world – are rare. But there are people who describe themselves as “skeptics” about various more specific domains, including self-professed “skeptics” about the reality of anthropogenic climate change. There is little to no philosophical literature that juxtaposes the climate change skeptic with the external world skeptic. While many “traditional” epistemologists assume that the external world skeptic poses a serious philosophical challenge in a way that the (...) climate change skeptic doesn’t, many “applied” or “social” epistemologists assume that there isn’t much to be learned from debates about the external world skeptic, finding her challenge to be distant from both common sense and real-world concerns. I try to show that both of these views are mistaken. The external world skeptic raises deep questions that are important for our everyday deliberation about what to believe, and there are significant structural parallels between the arguments for external world skepticism and those for at least a form of climate change skepticism that is idealized – but not too idealized! – from the views of flesh-and-blood climate change skeptics. As such, we have strong reasons to think in parallel about how to reply to both skeptics’ challenges. I thus finish by (briefly) considering how different widespread responses to the external world skeptic might or might not generalize happily to the climate change skeptic’s challenge. (shrink)

If it works, I can use Putnam’s vat argument to show that I have not always been a brain-in-a-vat. It is widely thought that the vat argument is of no use against closure scepticism – that is, scepticism motivated by arguments that appeal to a closure principle. This is because, even if I can use the vat argument to show that I have not always been a BIV, I cannot use it to show that I was not recently envatted, and (...) it is thought that the claim that I am not justified in thinking that I was not recently envatted is all that the closure sceptic requires. In this paper I first argue that scenarios in which I have been recently envatted are inadequate for the sceptic’s purposes, and so the standard argument that the vat argument is of no use against closure scepticism fails. I then argue that it is not possible to revise the standard argument to meet my objection. I conclude that, if it works, I can use the vat argument as a defence against closure scepticism. (shrink)

One common attitude toward abstract objects is a kind of platonism: a view on which those objects are mind-independent and causally inert. But there's an epistemological problem here: given any naturalistically respectable understanding of how our minds work, we can't be in any sort of contact with mind-independent, causally inert objects. So platonists, in order to avoid skepticism, tend to endorse epistemological theories on which knowledge is easy, in the sense that it requires no such contact—appeals to Boghossian’s notion of (...) epistemic analyticity are particularly common here, as are appeals to some broadly pragmatic account of the good standing of basic beliefs. I argue, though, that these appeals are hopeless: an argument adapted from the Benacerraf–Field challenge shows that, even if some such theory can deliver the verdict that our beliefs about abstract objects have some prima facie good standing, this good standing will inevitably be defeated. (shrink)

According to epistemic fallibilism, we cannot be certain of anything. According to the Christian tradition, faith comes with certainty. I develop this dilemma from recent accounts of fallibilism and various representatives of the Christian tradition. I then argue that on John Henry Newman's account of faith the dilemma is merely apparent. Finally, I develop Newman's account of the certainty that accompanies faith and is compatible with fallibilism.

Corroborative evidence may be understood as having two epistemic effects: a primary effect by which it offers direct evidence for some claim, and a secondary effect by which it bolsters the appraised probative, or evidential, value of some other piece of evidence for that claim. This paper argues that the bolstering effect of corroborative evidence is epistemically legitimate because corroboration provides a reason to count the belief based on the initial evidence as sensitive to, and safe from, defeat in a (...) way that it was not previously recognized to be. Discovering that our initial evidence tracks the truth in a way we previously did not recognize provides a reason to positively reappraise the probative value of that evidence. The final section of the paper relates the proposed sensitivity- and safety-based account of corroboration to an explanation-based account. (shrink)

Epistemologists have proposed various norms of assertion to explain when a speaker is in an epistemic position to assert a proposition. In this article I propose a distinct necessary condition on assertibility: that a speaker should assert only what she sensitively believes, where a subject's belief is sensitive just in case the subject would not hold it if it were false. I argue that the Sensitivity Rule underwrites simple explanations for three key features of assertibility that pose explanatory challenges to (...) other prominent proposals: the fact that assertibility is open under known entailment, the general impropriety of assertions that a lottery ticket has lost made purely on the basis of the speaker's knowledge of the odds, and the fact that assertibility varies widely with features of the conversational context. I close by considering three distinct roles the Sensitivity Rule might play in the overall theory of assertibility. (shrink)

Both sensitivity and safety theorists concur that their accounts should be relativized to the same method that one employs in the actual world. However, properly individuating methods has proven to be a tricky matter. In this regard, Nozick (Philosophical Explanations, Harvard University Press, Cambridge, 1981) proposes a Same-Experience-Same-Method Principle: if the experiences associated with two method tokens are the same, they are of the same type of method. This principle, however, has been widely rejected by recent safety and sensitivity theorists. (...) In this paper, I raise an argument in favor of Nozick: not endorsing the principle leads to some rather implausible consequences when certain skeptical scenarios are considered—i.e., scenarios in which skeptical possibilities are ‘close’. Additionally, this argument reveals some important lessons about skepticism in general and the place of modal accounts of knowledge in the internalism/externalism debate. (shrink)

This paper introduces and defends the paradigm response to external world skepticism. To understand it, consider an analogy. One of the hallmarks of being a bird is an ability to fly. A penguin lacks this hallmark and thus fails to be a paradigm bird. Likewise, there are various hallmarks of knowledge. Some of your external world beliefs lack some of these hallmarks, and thus fail to be paradigm cases of knowledge. Just as the inability of penguins to fly doesn’t prevent (...) them from being birds, likewise the lack of these hallmarks doesn’t prevent your beliefs from being knowledge. It just prevents them from being paradigm cases thereof. (shrink)