Contemporary philosophers nearly unanimously endorse knowledge reliabilism, the view that knowledge must be reliably produced. Leading reliabilists have suggested that reliabilism draws support from patterns in ordinary judgments and intuitions about knowledge, luck, reliability, and counterfactuals. That is, they have suggested a proto-reliabilist hypothesis about “commonsense” or “folk” epistemology. This paper reports nine experimental studies (N = 1262) that test the proto-reliabilist hypothesis by testing four of its principal implications. The main findings are that (a) commonsense fully embraces the possibility (...) of unreliable knowledge, (b) knowledge judgments are surprisingly insensitive to information about reliability, (c) “anti-luck” intuitions about knowledge have nothing to do with reliability specifically, and (d) reliabilists have mischaracterized the intuitive counterfactual properties of knowledge and their relation to reliability. When combined with the weakness of existing arguments for reliabilism and the recent emergence of well supported alternative views that predict the widespread existence of unreliable knowledge, the present findings are the final exhibit in a conclusive case for abandoning reliabilism in epistemology. I introduce an alternative theory of knowledge, abilism, which out-performs reliabilism and well explains all the available evidence. (shrink)

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)

I report two experiments studying the relationship among explicit judgments about what people see, know, and should assert. When an object of interest was surrounded by visibly similar items, it diminished people’s willingness to judge that an agent sees, knows, and should tell others that it is present. This supports the claim, made by many philosophers, that inhabiting a misleading environment intuitively decreases our willingness to attribute perception and knowledge. However, contrary to stronger claims made by some philosophers, inhabiting a (...) misleading environment does not lead to the opposite pattern whereby people deny perception and knowledge. Causal modeling suggests a specific psychological model of how explicit judgments about perception, knowledge, and assertability are made: knowledge attributions cause perception attributions, which in turn cause assertability attributions. These findings advance understanding of how these three important judgments are made, provide new evidence that knowledge is the norm of assertion, and highlight some important subtleties in folk epistemology. (shrink)

Centuries ago, Descartes and Locke initiated a foundational debate in epistemology over the relationship between knowledge, on the one hand, and practical factors, on the other. Descartes claimed that knowledge and practice are fundamentally separate. Locke claimed that knowledge and practice are fundamentally united. After a period of dormancy, their disagreement has reignited on the contemporary scene. Latter-day Lockeans claim that knowledge itself is essentially connected to, and perhaps even constituted by, practical factors such as how much is at stake, (...) how important the situation is, or how one should act. Latter-day Cartesians claim, by contrast, that knowledge is entirely constituted by truth-related factors such as truth, belief, and evidence. Each side has supported its case with claims about patterns in ordinary behavior and knowledge judgments. Lockeans argue that these patterns are best explained by positing a fundamental and direct link between knowledge and practical factors. Cartesians argue that the patterns can be equally well explained by positing an indirect link, entirely mediated by the traditional factors of truth, belief, and evidence, thereby rendering the Lockean hypothesis unnecessary. We argue that Cartesians are right about some practical factors, in particular stakes and how important a situation is, which have, at best, a modest indirect relationship to knowledge. However, Lockeans are right about actionability: whether a person should pursue a course of action is unquestionably very powerfully and directly connected to knowledge. (shrink)

Many philosophers claim that interesting forms of epistemic evaluation are insensitive to truth in a very specific way. Suppose that two possible agents believe the same proposition based on the same evidence. Either both are justified or neither is; either both have good evidence for holding the belief or neither does. This does not change if, on this particular occasion, it turns out that only one of the two agents has a true belief. Epitomizing this line of thought are thought (...) experiments about radically deceived “brains in vats.” It is widely and uncritically assumed that such a brain is equally justified as its normally embodied human “twin.” This “parity” intuition is the heart of truth-insensitive theories of core epistemological properties such as justification and rationality. Rejecting the parity intuition is considered radical and revisionist. In this paper, I show that exactly the opposite is true. The parity intuition is idiosyncratic and widely rejected. A brain in a vat is not justified and has worse evidence than its normally embodied counterpart. On nearly every ordinary way of evaluating beliefs, a false belief is significantly inferior to a true belief. Of all the evaluations studied here, only blamelessness is truth-insensitive. (shrink)

I review recent work from armchair and cross-cultural epistemology on whether humans possess a knowledge concept as part of a universal “folk epistemology.” The work from armchair epistemology fails because it mischaracterizes ordinary knowledge judgments. The work from cross-cultural epistemology provides some defeasible evidence for a universal folk epistemology. I argue that recent findings from comparative psychology establish that humans possess a species-typical knowledge concept. More specifically, recent work shows that knowledge attributions are a central part of primate social cognition, (...) used to predict others’ behavior and guide decision-making. The core primate knowledge concept is that of truth detection (across different sensory modalities) and retention (through memory) and may also include rudimentary forms of indirect truth discovery through inference. In virtue of their evolutionary heritage, humans inherited the primate social-cognitive system and thus share this core knowledge concept. (shrink)

Appeals to ordinary thought and talk are frequent in philosophy, perhaps nowhere more than in contemporary epistemology. When an epistemological theory implies serious error in “commonsense” or “folk” epistemology, it is counted as a cost of the view. Similarly, when an epistemological theory respects or vindicates deep patterns in commonsense epistemology, it is viewed as a benefit of the view. Philosophers typically rely on introspection and anecdotal social observation to support their characterizations of commonsense epistemology. But recent experimental research shows (...) that philosophers employing these methods often seriously mischaracterize commonsense. Based on these findings, I propose a fundamental change to standard practice in the field. Whether the fundamental goal of epistemology is descriptive or prescriptive, experimentation is an integral part of the project. (shrink)

From antiquity through the twentieth century, philosophers have hypothesized that, intuitively, it is harder to know negations than to know affirmations. This paper provides direct evidence for that hypothesis. In a series of studies, I found that people naturally view negations as harder to know than affirmations. Participants read simple scenarios and made judgments about truth, probability, belief, and knowledge. Participants were more likely to attribute knowledge of an outcome when framed affirmatively than when framed negatively. Participants did this even (...) though the affirmative and negative framings were logically equivalent. The asymmetry was unique to knowledge attributions: it did not occur when participants rated truth, probability, or belief. These findings show new consequences of negation on people’s judgments and reasoning and can inform philosophical theorizing about the ordinary concept of knowledge. (shrink)

A standard view in contemporary philosophy is that belief is involuntary, either as a matter of conceptual necessity or as a contingent fact of human psychology. We present seven experiments on patterns in ordinary folk-psychological judgments about belief. The results provide strong evidence that voluntary belief is conceptually possible and, granted minimal charitable assumptions about folk-psychological competence, provide some evidence that voluntary belief is psychologically possible. We also consider two hypotheses in an attempt to understand why many philosophers have been (...) tempted to view belief as involuntary: that belief is a prototype concept and that belief is a dual character concept. Altogether, our findings contribute to longstanding philosophical debates about the relationship between the will and the intellect, while also advancing scientific understanding of important social judgments. (shrink)

Experimental philosophers have investigated various ways in which non‐epistemic evaluations can affect knowledge attributions. For example, several teams of researchers (Beebe and Buckwalter 2010; Beebe and Jensen 2012; Schaffer and Knobe 2012; Beebe and Shea 2013; Buckwalter 2014b; Turri 2014) report that the goodness or badness of an agent’s action can affect whether the agent is taken to have certain kinds of knowledge. These findings raise important questions about how patterns of folk knowledge attributions should influence philosophical theorizing about knowledge.

Some incompatibilists about free will or moral responsibility and determinism would abandon their incompatibilism were they to learn that determinism is true. But is it reasonable to flip-flop in this way? In this article, we contend that it is and show what follows. The result is both a defense of a particular incompatibilist strategy and a general framework for assessing other cases of flip-flopping.

From antiquity through the twentieth century, philosophers have hypothesized that, intuitively, it is harder to know negations than to know affirmations. This paper provides direct evidence for that hypothesis. In a series of studies, I found that people naturally view negations as harder to know than affirmations. Participants read simple scenarios and made judgments about truth, probability, belief, and knowledge. Participants were more likely to attribute knowledge of an outcome when framed affirmatively than when framed negatively. Participants did this even (...) though the affirmative and negative framings were logically equivalent. The asymmetry was unique to knowledge attributions: it did not occur when participants rated truth, probability, or belief. These findings show new consequences of negation on people’s judgments and reasoning and can inform philosophical theorizing about the ordinary concept of knowledge. (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)

We report the results of four empirical studies designed to investigate the extent to which an epistemic closure principle for knowledge is reflected in folk epistemology. Previous work by Turri (2015a) suggested that our shared epistemic practices may only include a source-relative closure principle—one that applies to perceptual beliefs but not to inferential beliefs. We argue that the results of our studies provide reason for thinking that individuals are making a performance error when their knowledge attributions and denials conflict with (...) the closure principle. When we used research materials that overcome what we think are difficulties with Turri’s original materials, we found that participants did not reject closure. Furthermore, when we presented Turri’s original materials to non-philosophers with expertise in deductive reasoning (viz., professional mathematicians), they endorsed closure for both perceptual and inferential beliefs. Our results suggest that an unrestricted closure principle—one that applies to all beliefs, regardless of their source—provides a better model of folk patterns of knowledge attribution than a source-relative closure principle. (shrink)