Christina Starmans

How do people decide which claims should be considered mere beliefs and which count as knowledge? Although little is known about how people attribute knowledge to others, philosophical debate about the nature of knowledge may provide a starting point. Traditionally, a belief that is both true and justified was thought to constitute knowledge. However, philosophers now agree that this account is inadequate, due largely to a class of counterexamples (termed ‘‘Gettier cases’’) in which a person’s justified belief is true, but only due to luck. We report four experiments examining the effect of truth, justification, and ‘‘Gettiering’’ on people’s knowledge attributions. These experiments show that: (1) people attribute knowledge to others only when their beliefs are both true and justified; (2) in contrast to contemporary philosophers, people also attribute knowledge to others in Gettier situations; and (3) knowledge is not attributed in one class of Gettier cases, but only because the agent’s belief is based on ‘‘apparent’’ evidence. These findings suggest that the lay concept of knowledge is roughly consistent with the traditional account of knowledge as justified true belief, and also point to a major difference between the epistemic intuitions of laypeople and those of philosophers.

What makes someone the same person over time? There are (at least) two ways of understanding this question: A person can be the same in the sense of being very similar to how they used to be (similarity), or they can be the same in the sense of being the same individual (numerical identity). In recent years, several papers have claimed to explore the commonsense notion of numerical identity. However, we suggest here that these researchers have instead been studying similarity. We develop a novel method that uses simple intuitions about objects to illustrate these two notions of “same person”, and then asks which concept applies to instances of personal change. Across 4 studies (N = 2446), we find that these previously documented intuitions are best understood as reflecting judgments about similarity, not identity (Experiments 1 and 2). We then use this method to explore the situations in which participants do perceive a change in numerical identity. We find that when a person's entire brain (Experiments 3 and 4) or soul (Experiment 4) has been replaced with that of another person, the majority of participants judge that numerical identity has changed. However, we also note that a substantial minority of participants denied that identity had changed, opening new questions about the role of the body in intuitive judgments of personal identity.

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.

Nagel, San Juan, and Mar report an experiment investigating lay attributions of knowledge, belief, and justification. They suggest that, in keeping with the expectations of philosophers, but contra recent empirical findings [Starmans, C. & Friedman, O. (2012). The folk conception of knowledge. Cognition, 124, 272–283], laypeople consistently deny knowledge in Gettier cases, regardless of whether the beliefs are based on ‘apparent’ or ‘authentic’ evidence. In this reply, we point out that Nagel et al. employed a questioning method that biased participants to deny knowledge. Moreover, careful examination of participants’ responses reveals that they attributed knowledge in Gettier cases. We also note that Nagel et al. misconstrue the distinction between ‘apparent’ and ‘authentic’ evidence, and use scenarios that do not feature the structure that characterizes most Gettier cases. We conclude that NS&M’s findings are fully compatible with the claim that laypeople attribute knowledge in Gettier cases in general, but are significantly less likely to attribute knowledge when a belief is generated based on apparent evidence.

Although people own myriad objects, land, and even ideas, it is currently illegal to own other humans. This reluctance to view people as property raises interesting questions about our conceptions of people and about our conceptions of ownership. We suggest that one factor contributing to this reluctance is that humans are normally considered to be autonomous, and autonomy is incompatible with being owned by someone else. To investigate whether autonomy impacts judgments of ownership, participants recruited from Amazon Mechanical Turk read vignettes where a person paid for an entity or created it. Participants were less likely to judge that the entity was owned when it was described as autonomous compared with when it was described as non-autonomous, and this pattern held regardless of whether the entity was a human or an alien, a robot, or a human-like biological creation. The effect of autonomy was specific to judgments of whether entities were owned, and it did not influence judgments of the moral acceptability of paying for and keeping entities. These experiments also found that judgments of ownership were separately impacted by ontological type, with participants less likely to judge that humans are owned compared with other kinds of entities. A fourth experiment tested a further prediction of the autonomy account, and showed that participants are more likely to view a person as owned if he willingly sells himself. Together these findings show that attributions of autonomy constrain judgments of what can be owned. 2017 APA, all rights reserved)