lying

Deliberately making false statements with the intention to deceive or mislead. Lying may sometimes be justified; for example, for self-protection or to deceive the enemy in wartime.

The question of whether it is ever right to tell a lie has frequently been discussed by moral philosophers, especially with reference to difficult situations, such as whether a doctor should withhold the truth from a patient with a fatal disease or whether one should protect a friend or client with a lie when telling the truth would be a betrayal of confidence.

In pathological lying, the mendacity has no moral justification. The pathological liar is typically an impostor or swindler, adopting a false persona with the aim, say, of obtaining money under false pretences.