Donald Trump has doubled down on his claim that Joe Biden lacks the mental faculties to be president of the United States, implying his opponent in the approaching presidential election would be unable to pass a basic cognitive test.
As you might recall, Trump recently bragged about "acing" such a test, saying the doctors at Walter Reed Medical Centre were "very surprised" by how well he did.
"I actually took one when I – very recently, when I, when I was – the radical left were saying, is he all there? Is he all there? And I proved I was all there, because I got – I aced it. I aced the test," the President told Fox News host Sean Hannity earlier this month.
"(Biden) should take the same exact test. A very standard test. I took it at Walter Reed Medical Centre in front of doctors. And they were very surprised. They said, 'That's an unbelievable thing. Rarely does anybody do what you just did'.
"But he should take that same test."
The test in question is called the Montreal Cognitive Assessment. It is used as a screening tool to identify cognitive dysfunction, including early dementia and Alzheimer's disease.
During another interview with Fox News, which aired today, Trump once again challenged Biden to take it.
"Biden can't put two sentences together. They wheel him out, he goes up, he repeats, they ask him questions. He reads a teleprompter and then he goes back into his basement," the President told veteran political journalist Chris Wallace.
"Is Joe Biden senile?" Wallace asked.
"I don't want to say that. I'd say he's not competent to be president," Trump replied.
"To be president, you have to be sharp and tough and so many other things. He doesn't even come out of his basement.
"Joe doesn't even know he's alive, OK? He doesn't even know he's alive."
Wallace brought up a Fox News poll, published today, which asked respondents whether Trump and Biden had "the mental soundness to serve effectively as president". The results were not encouraging for either candidate.
Less than half of the respondents – 47 per cent – said Biden was mentally fit, and 39 per cent said he wasn't. The split was even worse for Trump, with 43 per cent saying he was fit and 51 per cent saying he wasn't.
"Well I tell you what, let's take a test. Let's take a test right now. Let's go down – Joe and I, we'll take a test. Let him take the same test that I took," Trump said.
Wallace seemed to have been anticipating that response.
"Incidentally, I took the test too, when I heard that you passed it," he said.
"Yeah, how did you do?" the President asked.
"It's not the hardest test. It has a picture and it asks, 'What's that?' And it's an elephant," Wallace replied, a little dryly, as an image of the test flashed up on screen.
The question Wallace referred to tasks the subject with identifying pictures of different animals. Another asks them to copy an image of a cube. A third asks them to read out a list of letters and tap their hand every time there's an A.
"See, that's all misrepresentation. It's all misrepresentation," Trump shot back.
"Because, yes, the first few questions are easy, but I bet you couldn't even answer the last five questions. I'll bet you couldn't. They get very hard, the last five questions."
"Well one of them was, 'Count backwards from 100 by seven'," Wallace said.
"Ninety-three," he added, as if to prove his own mental faculties.
"Let me tell you. You couldn't answer, you couldn't answer many of the questions. I guarantee you Joe Biden could not answer those questions. And I answered all 35 of those questions correctly," Trump said.
It's unclear which of the questions, exactly, Trump felt were "very hard", but he referred to "the last five". So, here they are.
The test's last question, asks the subject to identify the present date, month and year, along with the place and city they're currently in.
The second-last one asks them to recall five words that were used as part of a memory test a few minutes earlier.
The third-last one asks them to identify similarities between two words – for instance, "train" and "bicycle" are both forms of transport.
The fourth-last question gives the subject one minute to think of as many words as possible that start with a certain letter. They get the point if they can come up with at least 11.
And the fifth-last one asks them to repeat a short sentence word-for-word.
The interview lasted for 40 minutes, so there was time for Wallace to cover plenty of ground.
Asked how "crushing" it would be if he lost the election, Trump answered confidently.
"I won't lose," he said.
"The country, in the end, they're not going to have a man who's shot. He's shot. He's mentally shot.
"Let Biden sit through an interview like this. He'll be on the ground crying for mummy. He'll say, 'Mummy, mummy, please take me home'."
Trump also reiterated his belief that an increase in mail voting in November's election – which could be necessary, if the coronavirus pandemic is still rampant at that point – will lead to widespread voter fraud.
"Are you suggesting that you might not accept the results of the election?" Wallace asked.
"I have to see," said Trump.
Wallace pressed him for a more direct answer.
"I have to see," the President repeated.
"No, I'm not going to just say yes. I'm not going to say no. And I didn't last time either."
Trump took a potshot at his niece, Mary Trump, over the tell-all book she published last week, which paints her family as deeply dysfunctional and the President as psychologically damaged.
Much of the book focuses on Trump's father Fred, and the insidious influence he had on his children.
Dr Trump, a clinical psychologist with a PhD in Advanced Psychological Studies, diagnoses the long-dead Trump patriarch as a "high-functioning sociopath" and accuses him of "destroying" both Donald and his older brother Freddy.
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"My father liked to win. He was a very good man; he was a strong man. It's disgraceful that she said that," Trump told Wallace.
"She was not exactly a family favourite. We didn't have a lot of respect or like for her. I would have never said that, except she writes a book that is so stupid and so vicious, and it's a lie.
"For her to say, I think the word she used was 'psychopath', what a disgrace. She ought to be ashamed of herself."
Finally, Wallace confronted the President with a chart showing the massive increase in coronavirus cases across the US.
"That's because we have great testing, because we have the best testing in the world. If we didn't test, you wouldn't be able to show that chart," Trump said, repeating his most frequent explanation for the scale of America's outbreak.
"Sir, we have the seventh-highest mortality rate in the world. Our mortality rate is higher than Brazil, it's higher than Russia," Wallace pointed out.
"We have one of the lowest mortality rates in the world," Trump insisted.
"That's not true, sir," Wallace said.
If you have a spare 40 minutes, you can watch the entire interview here.