Tony Schwartz, the author who co-wrote Donald Trump's blockbuster book The Art of the Deal, spent 18 months in close proximity to the future president.
Schwartz appeared on CNN Wednesday, where he said he was totally unsurprised by how Trump has functioned as president, including his failed negotiation to get a border wall.
"I've not been surprised all the way through, as he's had one failure after another," Schwartz said.
Schwartz also said that Trump changes the moral compass of people around him and that he's "been in penance for 30 years over" what he did to enable his rise.
Trump profoundly affects the mood of everyone around him, Schwartz said, usually for the worse.
"It makes this an incredibly depressing time," Schwartz said. "I find myself angrier, moment to moment, day to day, than I would have been two years ago if there were no Trump. And I think that's across the population. He disrupts you, is what he does. Because he's so relentless. He comes at you and comes at you and comes at you... and he has no conscience."
Trump is a sociopath, Schwartz said.
"He is willing to say anything, to lie, to deceive, to distort, and not feel the slightest bit of guilt about it, and if it throws anybody off," Schwartz said. "He's a sociopath. He's sociopathic. Meaning, the absence of conscience. There isn't a soul in there... There isn't an internal barometer, there isn't a true north."