'Art of the Deal' co-author says Trump is deteriorating before our eyes ...

On Thursday, "Art of the Deal" co-author Tony Schwartz told MSNBC's Ari Melber that President Donald Trump is in a worse place emotionally than he's ever been.

"I think of the Trump that I knew in 1988, 1989," said Schwartz. "He was, relatively speaking, relaxed most of the time. He could occasionally be funny. And he had a kind of live or let live attitude, moment to moment. So long as I can do whatever I want, you do your thing. Now, he swings like a spinning top between megalomania and insecurity. And it's in inverse — the idea of rewriting weather reports, all of this stuff that you just shared — his megalomania is in inverse proportion to the level of security and confidence that he's feeling."

Melber noted, as an example, the president's recent Twitter attack on best-selling author and modeling icon Chrissy Teigen.

"What happened is he is so preoccupied with his sense of value or the absence of a sense of value," said Schwartz. "He lives inside the vast emptiness. He has to fill it all of the time. That is what you are watching when he goes after a Chrissy Teigen or weather people. Anything can be an affront to him and make him feel small. To retaliate he will go to the extremes. He will go to rage. He will go to demeaning. He will also go to lying. And you know ... he will go to tweeting."

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