Dhaka, June 24 -- When, how, and why do they develop this unpleasant habit? There is a considerable amount of evidence suggesting that most children first begin to lie around the ages of two or three. Anyone who has been around young little liars know that they aren't particularly skillful deceivers at that age.

Their lies are far-fetched, inconsistent with the evidence, or change dramatically over time. While they seem to understand the concept of planting a false belief in another's mind, they just haven't yet figured out the best ways to execute the dishonesty.

One can view lying as a complex cognitive and social task. In order to tell an effective lie, a child needs to understand that their goal is different from the goal of someone...