They were the same people before

Think, for example, of John Wayne Gacy, [...] Ted Bundy, [...] and Kenneth Bianchi.

We now diagnose most of these people as psychopaths, but the crucial point here is that their disorder and its behavior did not suddenly appear full-blown out of nowhere. They were the same people before they were caught as they were afterward. They are psychopaths now and they were psychopaths before.

This is a disturbing thought, because it suggests that the cases that come to the public's attention represent only the tip of a very large iceberg.

The rest of the iceberg is to be found nearly everywhere - in business, the home, the professions, the military, the arts, the entertainment industry, the news media, academe, and the blue-collar world. Millions of men, women, and children daily suffer terror, anxiety, pain, and humiliation at the hands of the psychopaths in their lives.

Tragically, these victims often cannot get other people to understand what they are going through...

- from Without Conscience, Robert D. Hare, 115