SIMON: Well, initially the title is scary. Like, “Ooh, Ted Bundy is next door!” Your point is that one in 25 people in North America is a sociopath—that it could be your next-door neighbor, your teacher, your co-worker, your . . . husband. Sociopathy is more prevalent than schizophrenia or anorexia.

STOUT: Right. It’s a much more common thing than most people realize.

SIMON: Explain the characteristics that a sociopath exhibits.

STOUT: Okay, the central trait of sociopathy is a complete lack of conscience, which is very difficult for most people to get their heads around, because those of us who do have a conscience can’t really imagine what it would be like if we didn’t. Most people think that deep down everybody has a conscience, and it turns out that’s just not true. So if you don’t have a conscience, what is your behavior like? Apparently, if you don’t have a conscience, if you don’t really . . . love, then the only thing that’s left for you is the game—it’s about controlling things.

SIMON: Manipulating people.

STOUT: Yes. Sometimes it doesn’t even have to be a large manipulation. And sociopaths are just like everybody else in that some of them are really brilliant, some of them are really stupid, and most of them are somewhere in between. Another thing I should point out is that sociopaths are not usually physically violent. A typical sociopath never kills anybody and doesn’t look like Charles Manson—they look like you and me and everybody else. You’re not looking for someone who’s recognizably evil or scary-looking, but rather someone who looks normal. Another lynchpin is dishonesty. Lying for the sake of lying. Lying just to see whether you can trick people. And sometimes telling larger lies to get larger effects. The other thing that needs to be stressed is that sociopaths are often extremely charming. They are people who are better than you and me at charming people, at being charismatic. I’ve heard this more often than I can count: “He was the most charming man I ever met,” or, “She was the sexiest woman I ever met,” or, “The most interesting person I ever met . . .” That’s because to learn to be charming is fairly easy—you can teach somebody to be charming and to learn human emotions—or to learn the behaviors that go with human emotions. A sociopath, a smart one, will study the way we emote, and will learn how to do that quite effectively.

SIMON: Is there a particular type of person that a sociopath picks out to manipulate?

STOUT: Well, the perfect victim, from the sociopath’s point of view, is the person who is smart enough and capable enough to do him some good in the world and who is also fun to manipulate. How much fun is it to manipulate someone who is stupid and incompetent? Another good person to manipulate is someone of high character, because that is also fun for the sociopath. On the other hand, the sociopath doesn’t want this person to be so savvy that he or she will immediately see him for who he is. He wants the person to be easily enough fooled to stick with him. This can be accomplished by looking for someone who is very, very loyal. Most of us consider loyalty to be a very positive trait—and it is a positive trait. But it also blinds people to some of the traits of the person they’re loyal to.