To lie is to intentionally mislead others when they expect honest communication. People lie so that others will form beliefs that are not true. The more consequential the beliefs--that is, the more a person's well-being depends upon a correct understanding of the world--the more consequential the lie.

Research suggests that all forms of lying--including white lies meant to spare the feelings of others--are associated with poorer-quality relationships.

A wasteland of embarrassment and social upheaval can be neatly avoided by following a single precept in life: Do not lie.

Once one commits to telling the truth, one begins to notice how unusual it is to meet someone who shares this commitment. Honest people are a refuge: You know they mean what they say; you know they will not say one thing to your face and another behind your back; you know they will tell you when they think you have failed--and for this reason their praise cannot be mistaken for mere flattery. Honesty is a gift we can give to others. It is also a source of power and an engine of simplicity. Knowing that we will attempt to tell the truth, whatever the circumstances, leaves us with little to prepare for. We can simply be ourselves. In committing to be honest with everyone, we commit to avoiding a wide range of long-term problems, but at the cost of occasional, short-term discomfort.

It can take practice to feel comfortable with this way of being in the world--to cancel plans, decline invitations, critique others' work, etc., all while being honest about what one is thinking and feeling. To do this is also to hold a mirror up to one's life--because a commitment to telling the truth requires that one pay attention to what the truth is in every moment. What sort of person are you? How judgmental, self-interested, or petty have you become? You might discover that some of your friendships are not really that--perhaps you habitually lie to avoid making plans, or fail to express your true opinions for fear of conflict. Whom, exactly, are you helping by living this way? You might find that certain relationships cannot be honestly maintained.

False encouragement is a kind of theft: it steals time, energy, and motivation a person could put toward some other purpose.

Lying is, almost by definition, a refusal to cooperate with others. It condenses a lack of trust and trustworthiness into a single act. It is both a failure of understanding and an unwillingness to be understood. To lie is to recoil from relationship.

Mental Accounting

Lies beget other lies. Unlike statements of fact, which require no further work on our part, lies must be continually protected from collisions with reality. When you tell the truth, you have nothing to keep track of. The world itself becomes your memory, and if questions arise, you can always point others back to it. You can even reconsider certain facts and honestly change your views. And you can openly discuss your confusion, conflicts, and doubts with all comers. In this way, a commitment to the truth is naturally purifying of error. But the liar must remember what he said, and to whom, and must take care to maintain his falsehoods in the future. This can require an extraordinary amount of work--all of which comes at the expense of authentic communication and free attention. The liar must weigh each new disclosure, whatever the source, to see whether it might damage the facade that he has built. And all these stresses accrue, whether or not anyone discovers that he has been lying.