Donald Trump has always been ignorant and irrational, but over the last few years, it’s clear that he is slowing down and becoming less coherent, according to the former president’s own biographer.

Tim O’Brien, who spent massive amounts of time with Trump before writing TrumpNation: The Art of Being the Donald, appeared on MSNBC on Saturday to discuss Trump’s recently reported “exhaustion.”

The host played videos of Trump slurring his words and failing to finish his sentences, and asked O’Brien his opinion.

“I think what is important is that, to a certain extent, he’s always been this way. He’s ignorant. He’s a racist. He’s irrational, a flamethrower,” the writer said. “He goes after people emotionally and not intellectually. And he’s been that way his whole life.”

He continued, saying, “What we have seen since 2020 is he is degrading.”

“His speech is slurring. His mind is slower and he’s tired at the end of the day and loses the plot and loses the narrative and his train of thought, and he’s dangerous.”

Later in the interview, O’Brien talks about Trump’s “bonkers political strategy” of continuing to play to his base.

“They are with him regardless of what he will do. He needs, I think, to convince people that he’s a rational actor, and he’s not,” he said. “And every time he has an opportunity to do it, whether he’s debating Kamala Harris or talking to someone on the stage in Chicago where the script should be about being rational and in command of the facts, he does not do it, in part because he’s not capable, but also because he does not want to and it drives his campaign managers bonkers.”

Watch below or click here.