Humans have been lying for as long as we have been writing – probably longer. Deception is a recurring theme in Greek mythology, with many stories about Dolos (the spirit of trickery and guile) and Apate (the goddess of fraud and deceit). The most famous example may be the trickery and deception involved in invading Troy, when the Greeks pretended to give up on war, leaving a large wooden horse behind on shore that was presented as a peace offering. When the Trojans were fast asleep, the Greek men that were hidden in the Trojan horse snuck out and conquered Troy.

Lying is not just something of the past; people still lie. Although we like to think of ourselves as honest people, and although we usually judge lying negatively, experimental research has demonstrated that the majority of people lie on a daily basis. For example, in two one-week diary studies by DePaulo et al (1996), people lied on average once or twice a day during their everyday interactions. In total, participants lied to approximately a third of the people that they interacted with over the course of the week. Although we tend to lie more in conversations with people that we’ll see again in the future (Tyler & Feldman, 2004), we also lie when interacting with strangers that we most likely will not encounter again. In a 10-minute long conversation with a complete stranger, people tended to tell about two lies on average (Tyler et al., 2006). These studies demonstrate that deception is a standard component of people’s everyday interactions, and has been for as long as we are aware.