FYI: I'll be utilizing the TV character to analyze, not the book character in the series by L.J. Smith.
Damon is the "bad" brother, for sure. He was born in Mystic Falls in 1840, 7 years before his brother Stephan. We've gotten glimpses of his human life from the show, and it's clear that he was impulsive, disrespectful of authority figures (in particular, his father), rebellious and careless. He craved the thrill of adventure and danger, and was often engaged in high risk-taking behavior like drinking, gambling (at boxing matches, etc), and womanizing.
As a vampire, all of those character traits are magnified. At the beginning of the show, he could only be described as sinister. He was ruthless and unsympathetic, had little regard for human life, and had no guilt or remorse with killing any of them. Very selfish, arrogant, proud, and manipulative. (Not a pretty picture on paper, but still in a pretty package. Am I right, or am I right, ladies? Look at that cutie smile!)
Now, as the show has just finished it's third season, Damon has shown more of a compassionate side and an ability to feel, especially where Elena (the show's heroine) is concerned. He still has a sadistic nature about him, and he's willing to go to any extreme to keep Elena safe. But he feels things for others besides his love interest, like his "friend" Alaric Salztman, whom he wanted to let "die in dignity," but who he had "killed" himself at least three times prior. Or glamoring Elena's brother Jeremy to forget the horrors he's experienced (again, for Elena, but he didn't have to do it). He also took a bite from Tyler instead of allowing Caroline to get bit.
But given the above considerations, Damon does fit the diagnosis for Antisocial Personality Disorder (APD). Here's a breakdown (the criteria Damon meets are in red):
A. There is a pervasive pattern of
disregard for and violation of the rights of others occurring since age
15 years, as indicated by three (or more) of the following:
(1) failure to conform to social norms
with respect to lawful behaviors as indicated by repeatedly performing
acts that are grounds for arrest (What's the death toll by Damon's hands up to now?)
(2) deceitfulness, as indicated by repeated lying, use of aliases, or conning others for personal profit or pleasure (Gosh, where to start? The moonstone, the white oak stakes, glamouring his "girlfriends.")
(3) impulsivity or failure to plan ahead (I think Damon's quite the planner when he wants to be, as evidenced by all the plots each episode to kill Klaus or any original, etc, but he does act on a gut level, killing Rick Saltzman several times because he got mad is a prime example.)
(4) irritability and aggressiveness, as indicated by repeated physical fights or assaults (Fights every episode, I believe, and an unlimited amount of brooding.)
(5) reckless disregard for safety of self or others (Possibly one of the worse/best examples was how he led his anchor girlfriend to her death at the studio. He often puts himself in impossible situations to survive.)
(6) consistent irresponsibility, as indicated by repeated failure to sustain consistent work behavior or honor financial obligations (He clearly did this as a human, carousing instead of being honorable. He doesn't have a job in TVD and he never honors his word unless it's to Elena.)
(7) lack of remorse, as indicated by being indifferent to or rationalizing having hurt, mistreated, or stolen from another (
(2) deceitfulness, as indicated by repeated lying, use of aliases, or conning others for personal profit or pleasure (Gosh, where to start? The moonstone, the white oak stakes, glamouring his "girlfriends.")
(3) impulsivity or failure to plan ahead (I think Damon's quite the planner when he wants to be, as evidenced by all the plots each episode to kill Klaus or any original, etc, but he does act on a gut level, killing Rick Saltzman several times because he got mad is a prime example.)
(4) irritability and aggressiveness, as indicated by repeated physical fights or assaults (Fights every episode, I believe, and an unlimited amount of brooding.)
(5) reckless disregard for safety of self or others (Possibly one of the worse/best examples was how he led his anchor girlfriend to her death at the studio. He often puts himself in impossible situations to survive.)
(6) consistent irresponsibility, as indicated by repeated failure to sustain consistent work behavior or honor financial obligations (He clearly did this as a human, carousing instead of being honorable. He doesn't have a job in TVD and he never honors his word unless it's to Elena.)
(7) lack of remorse, as indicated by being indifferent to or rationalizing having hurt, mistreated, or stolen from another (
B. The individual is at least age 18 years. (Damon is over 400 years old, but he was turned in his early twenties, so he's "frozen" there.)
C. There is evidence of Conduct Disorder with onset before age 15 years. (Yep, from his human history, this is likely.)
As you can see, you only need three traits to be considered APD, and Damon rocks out with all 7 criteria. I think it's important to note that Damon does not exhibit these traits all the time, which is why he wouldn't be considered a psychopath. He has taken responsibility for his behavior before, he has experienced remorse about past actions, and he can be very honest and reliable (when it suits him and it's about something or someone he cares a great deal about).
While this diagnosis isn't good news for my favorite character, you Stephan-lovers out there won't be all that thrilled with his diagnosis, either. Stay-tuned for that on Wednesday!
Let's Analyze: To contradict what I've just written, let's come up with some fantastic scenes to prove my point that Damon isn't all that "bad" of a guy. What scenes can you think of where Damon doesn't fit the criteria above?