A Bayesian framework for knowledge attribution: Evidence from semantic integration

Abstract

a b s t r a c tWe propose a Bayesian framework for the attribution of knowledge, and apply this framework to generate novel predictions about knowledge attribution for different types of ''Gettier cases'', in which an agent is led to a justified true belief yet has made erroneous assumptions. We tested these predictions using a paradigm based on semantic integration. We coded the frequencies with which participants falsely recalled the word ''thought'' as ''knew'' (or a near synonym), yielding an implicit measure of conceptual activation. Our experiments confirmed the predictions of our Bayesian account of knowledge attribution across three experiments. We found that Gettier cases due to counterfeit objects were not treated as knowledge (Experiment 1), but those due to intentionally-replaced evidence were (Experiment 2). Our findings are not well explained by an alternative account focused only on luck, because accidentally-replaced evidence activated the knowledge concept more strongly than did similar false belief cases (Experiment 3). We observed a consistent pattern of results across a number of different vignettes that varied the quality and type of evidence available to agents, the relative stakes involved, and surface details of content. Accordingly, the present findings establish basic phenomena surrounding people's knowledge attributions in Gettier cases, and provide explanations of these phenomena within a Bayesian framework.

Evidence for anti-intellectualism about know-how from a sentence recognition task

“…After reading a distractor story and answering comprehension questions about it, participants were asked to indicate whether a series of sentences had appeared in the story about the instructor. Following prior semantic integration designs (e.g., Powell et al 2014Powell et al , 2015Waskan et al 2014), our hypothesis was that the version of the story people read (i.e. the condition they were assigned to) would influence what they encoded about the instructor.…”

“…Specifically, we hypothesized that participants would incorrectly think that a sentence saying that an instructor knew how to perform a task (the critical sentence) was present in the story they read when the sentence fit with what they semantically encoded about the story (Bransford and Franks 1971;Powell et al 2014Powell et al , 2015Waskan et al 2014). By comparing participants' false alarm rates on the critical sentence across conditions, as well as their overall false alarms on other control sentences, we were able to measure the degree to which these stories differentially led participants to encode that the instructor knows how.…”

“…3 Rather than using a standard survey measure, we employed an implicit measure of conceptual activation called semantic integration (Gentner 1981;Powell et al 2014Powell et al , 2015Waskan et al 2014). Semantic integration is the cognitive process by which units of semantic information are combined to form more complex structured representations.…”

“…First, it does not appear that measures were taken to conceal the aim of the study from participants. When a study's aim can be guessed by its participants, the results may owe to demand characteristics, which are artifacts of the study design that lead participants to perform the study in a manner that is consistent with the experimental hypothesis (Firestone and Scholl 2014;Orne 1962;Powell et al 2015). When demand characteristics cannot be ruled out, it is difficult to determine whether participants' judgments provide evidence for the hypothesis in question or whether participants have merely guessed the aim of the study and behaved in a way consistent with their guess.…”

“…However, because people's judgments are downstream from their concepts, data gathered in this manner may reflect unthoughtful reactions to difficult philosophical issues rather than their intuitions or concepts (see Cullen 2010;Kauppinen 2007;Powell et al 2014Powell et al , 2015Sosa 2007 for similar criticisms).…”