I guess the unscientific layman’s explanation is that when practiced regularly, lying becomes an easy habit to fall into. In fact it becomes so much the norm that the liar doesn’t actually see what they do as lying. It becomes knit with their character and personality.
“…..American fraudster Frank Abagnale, played by Leonardo DiCaprio in the film Catch Me If You Can, started out swindling his father out of small change for date money and ended up impersonating an airline pilot, despite the admission that he “couldn’t fly a kite”.
Now scientists have uncovered an explanation for why telling a few porkies has the tendency to spiral out of control. The study suggests that telling small, insignificant lies desensitises the brain to dishonesty…, meaning that lying gradually feels more comfortable over time.
Tali Sharot, a neuroscientist at University College London and senior author, said: “Whether it’s evading tax, infidelity, doping in sports, making up data in science or financial fraud, deceivers often recall how small acts of dishonesty snowballed over time and they suddenly found themselves committing quite large crimes……” From porkies to whoppers: over time lies may desensitise brain to dishonesty