She studied extreme psychopaths. Here’s what it taught her about human nature | Abigail Marsh

• It's a very common misperception that humans are fundamentally selfish—meaning every motivation that drives us is based in a desire for what will benefit us, that we don't have any capacity for truly caring about other people. I think there are reasons to be confident that can't be true, and I think one of the most compelling is the existence of the disorder called 'psychopathy.'

So, people who are highly psychopathic genuinely don't care about other people's welfare. And so I think the fact that psychopathy exists is pretty clear evidence that people are not fundamentally selfish. In addition, we now know that psychopathy exists on a spectrum: so there's very psychopathic people, people in the middle, but also people who are sort of anti-psychopathic.

Most of that distribution of people definitely have the capacity to care for other people, and we've identified regions of the brain that specifically seem to encode the value of other people's welfare. I think it's really important for the reality of human nature based on the scientific literature to be better understood because trusting one another is a lot more enjoyable way to be, and it's more accurate, frankly, than being cynical.

And so to try to understand that better, I have been studying extreme populations of people who have done things in the real world that suggest they're unusually caring or unusually uncaring. My name is Abigail Marsh. I'm a professor of psychology and neuroscience at Georgetown University, and I study the neural and cognitive basis of empathy, altruism, and aggression.

The way we think about psychopathy now derives from the work of a psychiatrist named Hervey Cleckley, who was a really legendary clinician who spent many, many years studying people with psychopathy. He wrote a book called "The Mask of Sanity," and I think that title perfectly captures what it is that makes people with psychopathy unique, which is that they outwardly appear completely normal, even super normal.

They seem just like anybody else, but that really is a mask that's concealing inner profound deficits in emotion and the way that they engage with other people. In its extreme form, psychopathy can drive some of the most serious antisocial behavior and violence that we see. So, for example, the serial killer, Gary Ridgway, is perhaps the most psychopathic criminal. He killed dozens of young women over the course of a few decades.

We'll probably never know exactly how many. His behavior, and also the way he talked about them, made it clear just how little he valued their welfare. He didn't think that they mattered. The thing that I think unnerves people the most about serial killers like Gary Ridgway is just how normal they seem to everybody around them. They had families; they were known members of their community that were not caught for many years, in part, because nobody suspected that they could be doing such horrible things under the surface.

And that's a really good example of the mask of sanity. There's somebody doing things that are so awful under the surface that you would think there must be some sign of it externally. But in the case of some people with psychopathy, there really isn't. I get asked a lot, "What's the difference between the term psychopath and sociopath?" The main difference is that the term "psychopath" or "psychopathy" is a scientific and clinical term, and the term "sociopath" or "sociopathy" is not.

It's really important to emphasize that no clinician or scientist would ever refer to a person as a psychopath. We don't refer to people as their disease or as their disorder anymore. And so I refer to people who have psychopathy or who are psychopathic.

So what we know about psychopathy is it's a neurodevelopmental disorder; in its extreme form, affects probably 1% of people, maybe 2%. And it's pretty clear that people who go on to develop psychopathy are different from a very early age because their brain is developing differently. Psychopathy is best thought of as a constellation of personality traits, and the three key traits that compose psychopathy include, most importantly, a mean, callous disposition.

They really don't care about other people's welfare, and they'll do things that hurt other people to benefit themselves. They're certainly more likely to engage in various forms of aggression, especially when that aggression is aimed at achieving a goal.

So aggression can be divided into two broad categories: reactive aggression, which is the kind of aggression you show when somebody has made you mad, when you've been threatened, when you're frustrated, and then there's proactive aggression—it's deliberate aggression aimed at achieving a goal. So you threaten to hurt somebody in order to take their money or to take something that belongs to them. You threaten to reveal somebody's secrets so that they do what you want them to do.

That kind of aggression is really uniquely psychopathic. Second is a bold, socially-dominant personality. That boldness really reflects a fearless core. They don't seem to understand why other people feel fear. They're not good at recognizing when they're afraid, and if you have that problem, you're much more likely to do things that cause other people to feel fear without really understanding what the big deal is, and they just don't respond to risk and threat and punishment the way that other people do.

That happens to be one of the reasons that the polygraph doesn't work, because that's one of the things the polygraph is picking up on is fear responses when people are lying; people with psychopathy don't have those responses, not nearly as strongly, at least.

And third is being disinhibited or impulsive. They'll steal things from people, they'll steal things from stores. They'll lie often easily, and not really even for any reason. It's not really your fault if you have these traits. That's not to say that you don't deserve consequences. If you hurt somebody and you're psychopathic, I would never argue that—but I think it's really important that we balance our desire that they experience some consequences from what they've done with our understanding that they didn't choose to be this way.

On the other end of the spectrum are people who are anti-psychopathic, people who are, in some cases, extraordinarily altruistic, who do things to help others at real risk and cost to themselves, like rescuing people from drownings or fires or donating organs or bone marrow to other people. They're genuinely unselfish. And I hesitate to say that because the image that that conjures up in most people's minds is of somebody who's sort of saintly, right? They think of them as like a guardian angel or somehow superhuman.

It's not like they never swear. It's not like they never get, you know, mad when they're stuck in traffic. They're just ordinary people in most ways. The character of Iron Man is a really interesting example because, of course, he is very altruistic. He does a lot of things to help other people, but he doesn't seem like an altruist should seem, right? He's kind of a wise-cracker.

He's done some things that are less than savory in his past, but at core, you can tell that he really does care about the other people around him, and he will go to great lengths to help them. And so in some ways, I think that's a more realistic depiction of a genuinely altruistic person than the more sort of flat, one-dimensional old-school character like Superman.

Although extraordinary altruism is not a clinical condition, obviously, it is typified by traits that set altruists apart from other people. So first, their humility. They tend to think of themselves as just the same as anybody around them, despite the fact that they have actually done some pretty unusual things, and that seems to be a really core feature of altruism. If you think that everybody is equally special, helping others makes more sense.

They tend to believe in the goodness of other people. They're much less likely to believe that others can be truly evil. Finally, they seem to be more sensitive to other people's distress. They're more likely to empathize with and recognize other people's fear and also their pain.

What's really unusual about extraordinary altruists is that even when it comes to people who were very distant from them, people who were only acquaintances or even strangers, they still seem to value their welfare. We're supposed to help people who are close to us if they're in trouble, but if it's a perfect stranger, most of us don't see it as an obligation in the same way.

And yet extraordinary altruists, I don't think really see it that way. They really do think, "Well, this is a human being whose, you know, welfare is fundamentally important." If people are interested in knowing how altruistic versus psychopathic they are, there are a couple of tests out there on the internet that you can use to test yourself.

One of the better self-report tests of psychopathy is called the TriPM, and it's available on the website of PsychopathyIs. It is a brief but very well validated test of that bold, dominant, relatively callous personality that typifies psychopathy. And you can get a percentile score and find out where you fall. If you get a very low score on a psychopathy test, it may be a sign that you're highly altruistic.

But another way to test that is using a personality test called the HEXACO. What it really captures is the degree to which you believe that other people fundamentally matter versus are exploitable for your own good. There’s really good evidence that people can become more altruistic.

If you look at global trends, you see generally that people are donating more money over time. They're helping more strangers over time. One of the things that seems to make people become more generous is when they themselves are doing better. And I think because they have the psychological and physical resources to do so, so that's really good news because it means that policies that promote flourishing and well-being will probably also promote generosity.

But the best evidence for how people can become more generous is by just starting. And so I generally recommend that if people would like to become more altruistic, you think of some small feasible way to do things to help other people, and it should naturally proceed upward from there—because one of the absolute best things about altruism is how incredibly pleasant it is. It's such a source of joy for most people to help others. And that becomes a self-reinforcing process.

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