There's a subtle breakdown of trust. And there's a cumulative effect in society for all the times we don't tell the truth. Because politicians routinely break promises. When people can't depend on one another, you have to be ever vigilant and that takes a lot of energy. It's exhausting to be constantly on the defensive that way.
Lies are also a means for taking control away from someone else and co-opting it for oneself.
So, we'll tell a small lie for advantage in a competitive environment. All of these might come into play when we hide some family tragedy from grandma who's 85 year's old and has seen plenty of tragedy. Here, we want life to be neat, good, perceived as good and under control. Newman says that researchers have found that almost everyone lies on a regular basis, but mostly for altruistic reasons. From the President right down to a prospective employee, nonverbal communications expert Frank Horvath, Michigan State University professor of criminal justice, can usually tell who's lying.