When an adult refuses to let an injustice pass—stands up to a bully or asserts their rights—we call it principle. When a 15-year-old retaliates to an insult thrown in a school corridor, risking detention, we call it a failure to think ahead. It's easy to ascribe this to a not-yet-developed teena ge brain: a convenient shorthand for assuming they simply cannot weigh consequences properly. ...read more read less