"A half truth is a whole lie"
Wow, I used to say it to my Psychopath a lot...
Me, too. Here's an interesting quote, I think:
"Tell me what you regard as your greatest strength, so I will know how best to undermine you; tell me of your greatest fear, so I will know which I must force you to face; tell me what you cherish most, so I will know what to take from you; and tell me what you crave, so that I might deny you."
It's from a Star Wars novel, one of the bad guys explaining how he likes to handle personal relationships. May as well be a socio path introducing themselves.