Smith argues that, unlike other forms of evidence, naked statistical evidence fails to satisfy normic support. This is his solution to the puzzles of statistical evidence in legal proof. This paper focuses on Smith’s claim that DNA evidence in cold-hit cases does not satisfy normic support. I argue that if this claim is correct, virtually no other form of evidence used at trial can satisfy normic support. This is troublesome. I discuss a few ways in which Smith can respond.

This chapter reviews some faults of the theoretical literature and findings from the experimental literature on “Gettier” cases. Some “Gettier” cases are so poorly constructed that they are unsuitable for serious study. Some longstanding assumptions about how people tend to judge “Gettier” cases are false. Some “Gettier” cases are judged similarly to paradigmatic ignorance, whereas others are judged similarly to paradigmatic knowledge, rendering it a theoretically useless category. Experimental procedures can affect how people judge “Gettier” cases. Some important central tendencies (...) in judging “Gettier” cases appear to be robust against demographic variation in biological sex, age, language, and culture, although there could be some interesting differences related to culture and personality traits. Some remaining questions regarding Gettier’s cases, “Gettier” cases, and “the Gettier problem” concern the psychology and sociology of contemporary anglophone theoretical epistemology. Some remaining questions regarding the empirical study of knowledge judgments concern mechanisms underlying observed behavioral patterns. (shrink)

Radical skepticism is the view that we know nothing or at least next to nothing. Nearly no one actually believes that skepticism is true. Yet it has remained a serious topic of discussion for millennia and it looms large in popular culture. What explains its persistent and widespread appeal? How does the skeptic get us to doubt what we ordinarily take ourselves to know? I present evidence from two experiments that classic skeptical arguments gain potency from an interaction between two (...) factors. First, people evaluate inferential belief more harshly than perceptual belief. Second, people evaluate inferential belief more harshly when its content is negative (i.e., that something is not the case) than when it is positive (i.e., that something is the case). It just so happens that potent skeptical arguments tend to focus our attention on negative inferential beliefs, and we are especially prone to doubt that such beliefs count as knowledge. That is, our cognitive evaluations are biased against this specific combination of source and content. The skeptic sows seeds of doubt by exploiting this feature of our psychology. (shrink)

I review recent empirical findings on knowledge attributions in lottery cases and report a new experiment that advances our understanding of the topic. The main novel finding is that people deny knowledge in lottery cases because of an underlying qualitative difference in how they process probabilistic information. “Outside” information is generic and pertains to a base rate within a population. “Inside” information is specific and pertains to a particular item’s propensity. When an agent receives information that 99% of all lottery (...) tickets lose (outside information), people judge that she does not know that her ticket will lose. By contrast, when an agent receives information that her specific ticket is 99% likely to lose (inside information), people judge that she knows that her ticket will lose. Despite this difference in knowledge judgments, people rate the likelihood of her ticket losing the exact same in both cases (i.e. 99%). The results shed light on other factors affecting knowledge judgments in lottery cases, including formulaic expression and participants’ own estimation of whether it is true that the ticket will lose. The results also undermine previous hypotheses offered for knowledge denial in lottery cases, including the hypotheses that people deny knowledge because they either deny justification or acknowledge a chance for error. (shrink)

Nearly all success is due to some mix of ability and luck. But some successes we attribute to the agent’s ability, whereas others we attribute to luck. To better understand the criteria distinguishing credit from luck, we conducted a series of four studies on knowledge attributions. Knowledge is an achievement that involves reaching the truth. But many factors affecting the truth are beyond our control and reaching the truth is often partly due to luck. Which sorts of luck are compatible (...) with knowledge? We find that knowledge attributions are highly sensitive to lucky events that change the explanation for why a belief is true. By contrast, knowledge attributions are surprisingly insensitive to lucky events that threaten but ultimately fail to change the explanation for why a belief is true. These results shed light on our concept of knowledge, help explain apparent inconsistencies in prior work on knowledge attributions, and constitute progress toward a general understanding of the relation between success and luck. (shrink)

Five experiments demonstrate the central role of knowledge attributions in social evaluations. In Experiments 1–3, we manipulated whether an agent believes, is certain of, or knows a true proposition and asked people to rate whether the agent should perform a variety of actions. We found that knowledge, more so than belief or certainty, leads people to judge that the agent should act. In Experiments 4–5, we investigated whether attributions of knowledge or certainty can explain an important finding on how people (...) act based on statistical evidence, known as “the Wells effect”. We found that knowledge attributions, but not certainty attributions, mediate this effect on decision making. 2018 APA, all rights reserved). (shrink)

Evidence from life science, cognitive science, and philosophy supports the hypothesis that knowledge is a central norm of the human practice of assertion. However, to date, the experimental evidence supporting this hypothesis is limited to American anglophones. If the hypothesis is correct, then such findings will not be limited to one language or culture. Instead, we should find a strong connection between knowledge and assertability across human languages and cultures. To begin testing this prediction, we conducted three experiments on Koreans (...) in Korean. In each case, the findings replicated prior results observed in Americans and were corroborated by key findings from new replication studies on Americans using materials back-translated from Korean. These findings support the theory that there is a core, cross-culturally robust human practice of assertion and that, according to the rules of this practice, assertions should express knowledge. (shrink)

The epistemic closure principle says that knowledge is closed under known entailment. The closure principle is deeply implicated in numerous core debates in contemporary epistemology. Closure’s opponents claim that there are good theoretical reasons to abandon it. Closure’s proponents claim that it is a defining feature of ordinary thought and talk and, thus, abandoning it is radically revisionary. But evidence for these claims about ordinary practice has thus far been anecdotal. In this paper, I report five studies on the status (...) of epistemic closure in ordinary practice. Despite decades of widespread assumptions to the contrary in philosophy, ordinary practice is ambivalent about closure. Ordinary practice does not endorse an unqualified version of the epistemic closure principle, although it might endorse a source-relative version of the principle. In particular, whereas inferential knowledge is not viewed as closed under known entailment, perceptual knowledge might be. (shrink)

Nearly all philosophers agree that only true things can be known. But does this principle reflect actual patterns of ordinary usage? Several examples in ordinary language seem to show that ‘know’ is literally used non-factively. By contrast, this paper reports five experiments utilizing explicit paraphrasing tasks, which suggest that non-factive uses are actually not literal. Instead, they are better explained by a phenomenon known as protagonist projection. It is argued that armchair philosophical orthodoxy regarding the truth requirement for knowledge withstands (...) current empirical scrutiny. (shrink)

There is a widespread attitude in epistemology that, if you know on the basis of perception, then you couldn't have been wrong as a matter of chance. Despite the apparent intuitive plausibility of this attitude, which I'll refer to here as “stochastic infallibilism”, it fundamentally misunderstands the way that human perceptual systems actually work. Perhaps the most important lesson of signal detection theory (SDT) is that our percepts are inherently subject to random error, and here I'll highlight some key empirical (...) research that underscores this point. In doing so, it becomes clear that we are in fact quite willing to attribute knowledge to S that p even when S's perceptual belief that p could have been randomly false. In short, perceptual processes can randomly fail, and perceptual knowledge is stochastically fallible. The narrow implication here is that any epistemological account that entails stochastic infallibilism, like safety, is simply untenable. More broadly, this myth of stochastic infallibilism provides a valuable illustration of the importance of integrating empirical findings into epistemological thinking. (shrink)

Multiple epistemological programs make use of intuitive judgments pertaining to an individual’s ability to gain knowledge from exclusively probabilistic/statistical information. This paper argues that these judgments likely form without deference to such information, instead being a function of the degree to which having knowledge is representative of an agent. Thus, these judgments fit the pattern of formation via a representativeness heuristic, like that famously described by Kahneman and Tversky to explain similar probabilistic judgments. Given this broad insensitivity to probabilistic/statistical information, (...) it directly follows that these epistemic judgments are insensitive to a given agent’s epistemic status. From this, the paper concludes that, breaking with common epistemological practice, we cannot assume that such judgments are reliable. (shrink)

This paper puts forward a novel pluralist theory of epistemic justification that brings together two competing views in the literature—probabilistic and non-probabilistic accounts of justification. The first part of the paper motivates the new theory by arguing that neither probabilistic nor non-probabilistic accounts alone are wholly satisfactory. The second part puts forward what I call the Functional Theory of Justification. The key merit of the new theory is that it combines the most attractive features of both probabilistic and non-probabilistic accounts (...) of justification while avoiding their most serious shortcomings. The paper also provides a blueprint for future pluralist projects in epistemology. (shrink)

A ‘lottery belief’ is a belief that a particular ticket has lost a large, fair lottery, based on nothing more than the odds against it winning. The lottery paradox brings out a tension between the idea that lottery beliefs are justified and the idea that that one can always justifiably believe the deductive consequences of things that one justifiably believes – what is sometimes called the principle of closure. Many philosophers have treated the lottery paradox as an argument against the (...) second idea – but I make a case here that it is the first idea that should be given up. As I shall show, there are a number of independent arguments for denying that lottery beliefs are justified. (shrink)

We provide new findings that add to the growing body of empirical evidence that important epistemic intuitions converge across cultures. Specifically, we selected three recent studies conducted in the US that reported surprising effects of knowledge attribution among English speakers. We translated the vignettes used in those studies into Mandarin Chinese and Korean and then ran the studies with participants in Mainland China, Taiwan, and South Korea. We found that, strikingly, all three of the effects first obtained in the US (...) also emerged in the East Asian cultures we studied. Our findings not only cohere with but also provide—at least moderate—support for the existence of extensive convergences of important epistemic intuitions across cultures. (shrink)

Radical skepticism is the view that we know nothing, or at least next to nothing. Nearly no one actually believes that skepticism is true. Yet it has remained a serious topic of discussion for millennia and it looms large in popular culture. What explains its persistent and widespread appeal? How does the skeptic get us to doubt what we ordinarily take ourselves to know? I present evidence from two experiments that classic skeptical arguments gain potency from an interaction between two (...) factors. First, people evaluate inferential belief more harshly than perceptual belief. Second, people evaluate inferential belief more harshly when its content is negative (i.e. that something is not the case) than when it’s positive (i.e. that something is the case). It just so happens that potent skeptical arguments tend to focus our attention on negative inferential beliefs, and we are especially prone to doubt that such beliefs count as knowledge. That is, our cognitive evaluations are biased against this specific combination of source and content. The skeptic sows seeds of doubt by exploiting this feature of our psychology. (shrink)

Indicative judgments pertain to what is true. Epistemic modal judgments pertain to what must or might be true relative to a body of information. A standard view is that epistemic modals implicitly quantify over alternative possibilities, or ways things could turn out. On this view, a proposition must be true just in case it is true in all the possibilities consistent with the available information, and a proposition might be true just in case it is true in at least one (...) possibility consistent with the available information. I report three experiments testing this view of epistemic modals. The results show that although modal judgments are sensitive to information about alternative possibilities, the standard quantification theory mischaracterizes the ordinary meaning of modals. I then report two more experiments testing the hypothesis that epistemic modals express willingness to attribute knowledge based on the available information. The results support this hypothesis. The results also show that the difference between “inside” and “outside” probabilistic information, familiar from the judgment and decision-making literature, affects epistemic modal judgments. (shrink)

Academics across widely ranging disciplines all pursue knowledge, but they do so using vastly different methods. Do these academics therefore also have different ideas about when someone possesses knowledge? Recent experimental findings suggest that intuitions about when individuals have knowledge may vary across groups; in particular, the concept of knowledge espoused by the discipline of philosophy may not align with the concept held by laypeople. Across two studies, we investigate the concept of knowledge held by academics across seven disciplines (N (...) = 1,581) and compare these judgments to those of philosophers (N = 204) and laypeople (N = 336). We find that academics and laypeople share a similar concept of knowledge, while philosophers have a substantially different concept. These experiments show that (a) in contrast to philosophers, other academics and laypeople attribute knowledge to others in some “Gettier” situations; (b) academics and laypeople are much less likely to attribute knowledge when reminded of the possibility of error, but philosophers are not affected by this reminder; and (c) non‐philosophy academics are overall more skeptical about knowledge than laypeople or philosophers. These findings suggest that academics across a wide range of disciplines share a similar concept of knowledge, and that this concept aligns closely with the intuitions held by laypeople, and differs considerably from the concept of knowledge described in the philosophical literature, as well as the epistemic intuitions of philosophers themselves. (shrink)

Epistemologists have long believed that epistemic luck undermines propositional knowledge. Action theorists have long believed that agentive luck undermines intentional action. But is there a relationship between agentive luck and epistemic luck? While agentive luck and epistemic luck have been widely thought to be independent phenomena, we argue that agentive luck has an epistemic dimension. We present several thought experiments where epistemic luck seems to undermine both knowledge-how and intentional action and we report experimental results that corroborate these judgments. These (...) findings have implications for the role of knowledge in a theory of intentional action and for debates about the nature of knowledge-how and the significance of knowledge representation in folk psychology. (shrink)

In this paper, we present the results of two surveys that investigate subjects’ judgments about what can be known or justifiably believed about lottery outcomes on the basis of statistical evidence, testimonial evidence, and “mixed” evidence, while considering possible anchoring and priming effects. We discuss these results in light of seven distinct hypotheses that capture various claims made by philosophers about lay people’s lottery judgments. We conclude by summarizing the main findings, pointing to future research, and comparing our findings to (...) recent studies by Turri and Friedman. (shrink)