People with what we call mental illness can indeed serve well, and people who have no discernible mental illness - and that may be true of Trump - may not be able to serve, may be quite unfit. So it isn't always the question of a psychiatric diagnosis. It's really a question of what psychological and other traits render one unfit or dangerous.

Yes, I've been very preoccupied with the survivor all through my work.

There is a movement of more people recognizing global warming as a danger, recognizing the human contribution to global warming, recognizing the necessity for doing something about it. So there's a trend in that direction, and that trend is consistent with what a climate swerve - which is, as we're both saying, a mindset.

But I spent just two calendar years at Cornell University, though it was covering more than three years of work, and then went to medical school and did become interested in psychiatry, and even helped form a kind of psychiatry club in medical school.

In early psychoanalytic thought, narcissism was - and still, of course, is - self-love. The early psychoanalysts used to talk of libido directed at the self. That now feels a little quaint, that kind of language. But it does include the most fierce and self-displaying form of one's individual self. And in this way, it can be dangerous. When you look at Donald Trump, you can really see someone who's destructive to any form of life enhancement in virtually every area. And if that's what Fromm means by malignant narcissism, then it definitely applies.

I never quite envisioned myself a proper doctor under that white coat, but I was interested in the idea of healing and in the psychological dimension rather early on.

We have a duty to warn on an individual basis if we are treating someone who may be dangerous to herself or to others - a duty to warn people who are in danger from that person. We feel it's our duty to warn the country about the danger of this president. If we think we have learned something about Donald Trump and his psychology that is dangerous to the country, yes, we have an obligation to say so.