On a recent episode of the CW's Vampire Diaries, heroine Elena Gilbert orders antihero Damon Salvatore not to kill someone. When he doesn't immediately agree, she sneers, "I forgot that I was speaking to a psychotic mind that snaps and kills people impulsively."
Elena got her psych wrong.
What Elena meant was "psychopathic," not "psychotic." And while the two words may look and sound somewhat alike, they mean very different things. Unfortunately, the mistake is one a lot of writers make, so here's your quick guide to using both words properly.
Someone who is psychotic has lost contact with reality the way most people experience it. He probably has hallucinations (seeing, hearing, feeling, smelling, or tasting things that aren't there) and/or delusions (fixed beliefs not based in reality). As a result, his behavior may be unusual or even bizarre.
While Damon may not like reality from time to time, he's definitely in contact with it, so he's not psychotic.
Psychopathy is currently (and some say inadequately) diagnosed by therapists using the term Antisocial Personality Disorder (APD). Unlike the average person with APD, however, psychopaths do more than violate other people's rights without feeling particularly bad about it. Psychopaths destroy other people's lives — they lie, con, betray, cheat, steal, maim, murder, and anything else that will keep them entertained and on top. They're parasitic, shallow, and callous, lie pathologically, take no responsibility for their behaviors, and have no realistic long-term goals. They're outrageously unreliable. To be fair, because they're impulsive and quick-tempered, they may seem to "snap" and kill impulsively, the way Elena describes.
While Damon's behavior bears more than a passing resemblance to the description above at times, he isn't really psychopathic: he cares too much for others and what happens to them. He's also capable of taking responsibility for his behaviors, experiences remorse, doesn't have a parasitic lifestyle, and is extremely reliable when something (or someone) is important to him.
While an individual needs to meet only some of the criteria to be diagnosed with a disorder like APD, to be labelled a true psychopath (using Hare's Psychopathy Checklist, the PCL-R), he must fit the entire profile. Finally, psychopaths aren't just psychopaths sometimes. Their brains are different from other people's. The amygdala and the orbitofrontal cortext (OFC), for example, show disrupted functioning, which leads to reduced ability to learn from experience and poor decision-making skills. All the time.
So Damon isn't a psychopath, either.
Not that he'd probably have issues with people thinking he is. "I'm the most dangerous thing you're ever likely to encounter in your life," he's said. In fact, since he's always trying to convince people that he doesn't care about anyone except himself, knowing what "psychopathic" means would have given him a nice comeback to Elena's "psychotic" jibe. Cocksure and self-amused as always, he might have responded with his characteristic smirk and, "I think you meant psychopathic."