DAVID GREENE, HOST:
President Trump spent part of the weekend touting mental stability as one of his greatest assets, along with being, quote, "like, really smart." His tweets came after last week's publication of "Fire And Fury," an inside look at the Trump administration by journalist Michael Wolff, who characterized White House staffers as questioning the president's stability. Administration officials fought back over the weekend. This is CIA Director Mike Pompeo on "Fox News Sunday" talking about the president's fitness to lead.
(SOUNDBITE OF TV SHOW, "FOX NEWS SUNDAY")
MIKE POMPEO: It's such just a ludicrous question. All right? These are from people who just have not yet accepted the fact that President Trump is the United States president. And I'm sorry for them.
GREENE: But discussing mental health as a measure of presidential competency can actually be pretty complicated, and NPR science correspondent Jon Hamilton is here to talk about it. Hey, Jon.
JON HAMILTON, BYLINE: Hey.
GREENE: So you've been reporting on this, and, I mean, there's certainly been all these armchair diagnoses of President Trump. And you have psychologists and psychiatrists telling you that that's not such a good thing.
HAMILTON: Well, what they told me is it's pretty hard to diagnose somebody from reading their tweets, which I guess should not be a revelation, right? You really have to do a pretty thorough examination of somebody.
GREENE: Tweets are a limited body of data.
HAMILTON: A limited body of data would be safe to say. And, also, it is considered unethical by both the American Psychiatric Association and the American Psychological Association. And the reason goes back to something, it's known as the Goldwater rule. When Barry Goldwater was running for president in the 1960s, a magazine actually polled psychiatrists about whether he was psychologically unfit to be president. Some said he was not fit to be president, and the magazine was sued and lost. And so ever since then those associations, those groups have decided that it's not good to opine about somebody you've not examined in person. However, I should say, there is a small group of mental health professionals who have decided that their - what they would say their duty to warn is more important than those rules.
GREENE: Can we learn anything from the cases of former presidents on this topic?
HAMILTON: You can learn that mental illness, mental problems are pretty common. Which again should not be a revelation.
GREENE: Common among U.S. presidents?
HAMILTON: Yes. Yes, in fact, there was a study a few years ago that found that nearly half of the presidents before 1974 had some diagnosable conditions. And you've also had lots of armchair diagnoses of people even more recently. You know, you hear people saying Bill Clinton was a narcissist, Richard Nixon was paranoid. Although, actually, there's better evidence that he had alcohol problems that were pretty severe late in his term before he left. Lyndon Johnson was emotionally unstable, John F. Kennedy had psychopathic trades. And of course the most famous is Abraham Lincoln, who was suicidally depressed during periods of his life.
GREENE: Well, if that's the case, if past presidents have had mental health struggles, I mean, it feels like there's a much more vocal response when it comes to Donald Trump. But why is that, and what are we seeing here?
HAMILTON: Well, you know, Trump is unquestionably a polarizing figure, and that may be part of it. He is clearly redefining the presidency and what presidents do. But I think more than that what you're seeing is that his public exposure is so much. I mean, we're getting inside the guy's head in real time when he tweets. You know, we're hearing what he thinks, and we have a 24-hour news cycle. And also we have a White House where people seem very open to speaking about every little thing that happens, every action of the president. And that simply was not happening in previous administrations.
GREENE: The cable news era was not there in previous administrations...
HAMILTON: Not so much.
GREENE: ...Going back very far. NPR science correspondent Jon Hamilton, thanks for your reporting. We appreciate it.
HAMILTON: Thank you.