Evidence that saying something false is essential to lying.

The Truth About Lying

Turri, A., & Turri, J. (2015). The truth about lying. Cognition, 138(C), 161–168.

Abstract

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.