The standard view in social science and philosophy is that lying does not require the liar's assertion to be false, only that the liar believes it to be false. We conducted three experiments to test whether lying requires falsity. Overall, the results suggest that it does. We discuss some implications for social scientists working on social judgments, research on lie detection, and public moral discourse.

Researchers have debated whether there is a relationship between a statement's truthvalue and whether it counts as a lie. One view is that a statement being objectively false is essential to whether it counts as a lie; the opposing view is that a statement's objective truth-value is inessential to whether it counts as a lie. We report five behavioral experiments that use a novel range of behavioral measures to address this issue. In each case, we found evidence of a relationship. A statement's truth-value affects how quickly people judge whether it is a lie (Experiment 1). When people consider the matter carefully and are told that they might need to justify their answer, they are more likely to categorize a statement as a lie when it is false than when it is true (Experiment 2). When given options that inhibit perspective-taking, people tend to not categorize deceptively motivated statements as lies when they are true, even though they still categorize them as lies when they are false (Experiment 3). Categorizing a speaker as "lying" leads people to strongly infer that the speaker's statement is false (Experiment 4). People are more likely to spontaneously categorize a statement as a lie when it is false than when it is true (Experiment 5).We discuss four different interpretations of relevant findings to date. At present, the best supported interpretation might be that the ordinary lying concept is a prototype concept, with falsity being a centrally important element of the prototypical lie.

A standard view in social science and philosophy is that a lie is a dishonest assertion: to lie is to assert something that you think is false in order to deceive your audience. We report four behavioral experiments designed to evaluate some aspects of this view. Participants read short scenarios and judged several features of interest, including whether an agent lied. We found evidence that ordinary lie attributions can be influenced by aspects of audience uptake, are based on judging that the agent made an assertion (assertion attributions), and, at least in some contexts, are not based on attributions of deceptive intent. The finding on assertion attributions is predicted by the standard view, but the finding on intent attributions is not. These results help to further clarify the ordinary concept of lying and shed light on the psychological processes involved in ordinary lie attributions and related judgments.