Donald Trump's Art of the Deal Ghostwriter Says Former President Is 'Not Capable of Remorse'

Showtime Tony Schwartz

Donald Trump is "not capable of remorse," says the ghostwriter who helped the former president write his 1987 memoir.

In a clip shared exclusively with PEOPLE, Tony Schwartz, who helped pen Trump's book The Art of the Deal, tells Showtime's political documentary series The Circus that, according to his experience, the 45th president "is so deeply sociopathic that I don't think there is any capacity for empathy or any capacity for remorse."

Schwartz, 68, shares his thoughts on Trump and his much-scrutinized reaction to the deadly Jan. 6 riot in the U.S. Capitol building during an extended interview cut from the latest episode of The Circus, which aired on Sunday.

Speaking with host Jennifer Palmieri, the former White House communications director who held a similar role with Hillary Clinton's 2016 campaign, Schwartz says he has little doubt that the ex-president was "unquestionably excited" at the images from the riot, which left five people dead.

"He is by instinct an autocrat," Schwartz says. "He does want to bring down as many people with him, who he believes oppose him, as he possibly can if he has to go down."

Trump is the "least reflective human being" he thinks he's ever met, Schwartz says.

The writer also says that within 15 minutes after sitting down together for an interview while working on the memoir, Trump got up and said, "I've had enough of this."

"When I started interviewing Trump, his attention span turned out to be in the minutes maximum," Schwartz recalls. "He was already quite resistant."

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Since the Jan. 6 riot, Trump has largely avoided being seen in public — outside of one visit to the southern border and leaving the White House on Wednesday.

Trump was impeached for a second time for his role in drumming up the crowd in the moments before the riot and he's been banned from all major social platforms since, out of concern he might incite more violence.

MANDEL NGAN/AFP via Getty Donald Trump

The Jan. 6 insurrection took place after Trump told a crowd of supporters to "fight like hell" and encouraged them to go to the U.S. Capitol building, where lawmakers were in a joint session to confirm President Joe Biden's election.

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After the Capitol attack, Trump spent his final two weeks in office largely secluded from public view, reportedly still steaming over his election loss.

The former president's daily schedules were mostly empty since the new year, besides a vague disclaimer alleging that Trump would "make many calls and have many meetings."

Trump's political and personal futures remain unclear, after leaving the White House on Wednesday and retreating to his private Mar-A-Lago club in Florida.

"He's a defeated man," Schwartz says. "But the fact that his voice is a little low doesn't mean that an hour from now he won't be back to shouting as loud as he can, full of conviction that he's going to prevail somehow in the end."

The Circus airs Sundays on Showtime.