We all lie, all the time. It causes problems, to say the least. So why do we do it?

It boils down to the shifting sands of the self and trying to look good both to ourselves and others, experts say.

For instance, In one experiment, Feldman put two strangers in a room together. They were videotaped while they conversed. Later, independently, each was asked to view the tape and identify anything they had said that was not entirely accurate.

The study, published in the Journal of Basic and Applied Psychology, found that 60 percent of people had lied at least once during the 10-minute conversation, saying an average of 2.92 inaccurate things.

Men lie no more than women, but they tend to lie to make themselves look better, while women are more likely to lie to make the other person feel better.

Extroverts tend to lie more than introverts, Feldman found in similar research involving a job-interview situation.

Self-esteem and threats to our sense of self are also drivers when it comes to lying to co-workers, rather than strangers, says Jennifer Argo of the University of Alberta.

A recent study she co-authored showed that people are even more willing to lie to coworkers than they are to strangers.

The experiment involved reading a scenario to a subject, telling them they had paid more than a coworker for the same new car. When the coworker, in the scenario, mentioned what they had paid, $200 or $2,000 more in different versions of the experiment, the subject was asked to report how they would respond.

Argo found that her subjects were more willing to lie when the price difference was small and when they were talking to a coworker rather than to a stranger.

Consumers lie to protect their public and private selves, she wrote in the Journal of Consumer Research with her colleagues from the University of Calgary and University of British Columbia.

Argo said she was surprised that people are so willing to lie to someone they know even over a small price discrepancy.