According to Martha Stout in The Sociopath Next Door, one in 25 Americans is a bona fide sociopath, utterly lacking in conscience and real feelings toward others. Her research indicates that such guiltlessness results from a confluence of factors. Besides genetics, it is engendered by nurture and perverse cultural norms. Is there a sociopath living next door to you? Read on.

What prompted you to write this book?

I will confess that, like nearly everyone else, I've encountered sociopaths in my personal life. I can tell you that the character in the book whom I call Doreen Littlefield—the fraudulent psychologist who deliberately torments a fragile psychiatric inpatient—is someone I knew personally when I was a novice psychologist. But my motivation mainly came from listening to the life stories of my patients, most of whom were psychologically wounded by other human beings; most of these perpetrators were sociopaths. I wanted to write a book that would clearly describe the problem and help good people identify the sociopaths around them, hopefully before these good people could become victims.

Can you recap your 13 rules of dealing with sociopaths in everyday life?

The first rule is that one must accept the fact that, unsavory as it is, some people simply have no conscience and that these people tend to be very "everyday." Secondly, it is important to learn to use your own judgment about people instead of relying on roles and labels to inform you about a person's moral character. The third rule is to practice the Rule of Threes when considering a new relationship in your life. Three lies, and you should be concerned that you are hooking up with a liar. The fourth rule is to question authority. The fifth rule is to suspect flattery. The sixth rule says that, if necessary, you should redefine your concept of respect. The seventh rule is, simply, don't join the game. And related to this, the eighth rule is to avoid the sociopath altogether. Rule nine is to question your tendency to pity too easily. Number ten: do not try to redeem the sociopath. Also, number 11, never agree, out of pity or for any other reason, to help a sociopath conceal his or her true character from other people. Rule number 12 is do not allow someone without a conscience to convince you that humanity is a failure. And rule number 13 is an old saw, but true nonetheless: living well is the best revenge.

I think you've put a whole new slant on the self-help genre. Do you see your project as being unique?

With the exception of my "Thirteen Rules for Dealing with Sociopaths," the book does not say, "Do this." Instead, the book says, "Think about this." I wanted people to think about what sociopathy is and in thinking about it, in reading true stories aboutit, and in imagining how they would feel themselves if they had this profound deficit, to realize that the presence in the human population of this condition explains a very great deal of what we observe in our world. If the book is unique, it is because I have defined conscience psychologically. Conscience is an emotion that influences our behavior toward other living beings, because it is based in our capacity to love.

Lynne Maxwell, Villanova Univ. Sch. of Law Lib., PA