With the nuclear threat we know that if sufficient weapons are used, human civilization - all of humankind - could be extinguished literally by "nuclear winter." So we have to see ourselves as part of the ultimate human group, just as we have to do with global warming.

There are people who believe that there should be a standard psychiatric examination for every presidential candidate and for every president. But these are difficult issues because they can't ever be entirely psychiatric. They're inevitably political as well. I personally believe that ultimately ridding the country of a dangerous president or one who's unfit is ultimately a political matter, but that psychological professionals can contribute in valuable ways to that decision.

There's more and more recognition that a carbon economy is dangerous to us economically. And there is increasing recognition that renewable fuels have economic value as well as obvious value for our health and our well-being and our survival. In fact, as you know, the economic revolution in renewable fuels has been impressive. It really had not been anticipated.

I don't have the feeling that as a very young person I read books that absolutely made their mark on my mind.

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.

Trump has a mind that in many ways is always under duress, because he's always seeking to be accepted, loved. He sees himself as constantly victimized by others and by the society, from which he sees himself as fighting back. So there's always an intensity to his destructive behavior that could contribute to his false beliefs.

Donald Trump gives the impression that he would like to govern by decree. He has that impulse in him and he wants to be a savior, so he says, in his famous phrase, "Only I can fix it!" That's a strange and weird statement for anybody to make, but it's central to Trump's sense of self and self-presentation. And I think that has a lot to do with his identification with dictators. No matter how many they kill and no matter what else they do, they have this capacity to rule by decree without any interference by legislators or courts.