The person, however, who seems to feel compelled to lie about both the small and large stuff has a problem. We often call these folks pathological liars (which is a description, not a diagnosis). They lie to protect themselves, look good, gain financially or socially and avoid punishment.
Quite often the person who has been deceived knows that this type of liar has to a certain extent deluded him or herself and is therefore to be somewhat pitied.A much more troubling group is those who lie a lot — and knowingly — for personal gain.
These people may have a diagnosis called antisocial personality disorder, also known as being a sociopath, and often get into scrapes with the law. Lying often gets worse with the passage of time. When you get away with a lie it often impels you to continue your deceptions. Also, liars often find themselves perpetrating more untruths to cover themselves.
Why do we dislike liars, especially sociopaths, so much? It’s a matter of trust.
Serious deception often makes it impossible for us to trust another person again. Because the issue of trust is on the line, coming clean about the lie as soon as possible is the best way to mend fences.
If the truth only comes out once it is forced, repair of trust is far less likely.
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