With two weeks to go before the presidential election, we know more about the psychology of Republican presidential nominee Donald Trump than perhaps we’ve ever known about a presidential nominee in the modern era. And what we’ve discovered is that Trump is exactly what he’s appeared to be his entire public life: a black hole of ravening ego.

Interview tapes published by the New York Times on Tuesday offer a certain amount of insight into how Trump sees himself. The interviews, conducted in 2014 by Michael D’Antonio for his biography of Trump, show a striking admission from the current Republican nominee:

“No, I don’t want to think about it,” he said when Mr. D’Antonio asked him to contemplate the meaning of his life. “I don’t like to analyze myself because I might not like what I see.”

It’s striking because it isn’t surprising. It’s simply a confirmation of one of the biggest concerns raised by the potential of a Trump presidency: that Trump simply can’t handle criticism or dissent — even from himself.

The takeaway from Trump’s introspection, it turns out, is how profoundly un-introspective he is: all shiny surface but no reflection.

This is the best proof we’re ever going to get that there really is only one Donald Trump. But it also crystallizes one of the reasons to fear he would be a singularly awful president: He has no more appetite for things he might not like to see being shown to him by others. And so, inevitably, he leaves himself surrounded by sycophants.

Donald Trump actively shuts out people who tell him things he doesn’t want to hear

When you are doing the wrong thing, you need people who will put you on course-correct.

This is true if you are a leader of any organization. It is especially true if you are the leader of the world’s only remaining superpower.

If President Trump is supervising a military campaign that is not accomplishing its objectives, he needs military commanders who will tell him this, and he needs to listen to them so he can change course. If the US economy has a rough month, President Trump needs to be able to sit in a briefing, hear — and accept — the weak jobs numbers, and be willing to entertain suggestions for anything that could be done better.

And the worse things get, the more willing a leader should be to entertain criticisms of what he’s done so far.

That is literally the opposite of what Trump has done.

When he was a competitive candidate, he seemed open-minded to a fault — allegedly prone to adopting the opinion of whomever he’d spoken to last. But the worse things have gone for Trump, the less willing he’s been to listen to suggestions about how he might improve.

Indeed, in Trump’s worst moments he’s forced his subordinates and allies to defend him to the hilt — even against their own better judgment.

During some of Trump’s worst news cycles — his attack on Judge Gonzalo Curiel, his poorly reviewed first debate, his hints last week that he might not accept the results of the election — some of his campaign surrogates have tried to minimize the damage: playing down Trump’s remarks, admitting that he made a mistake, trying to get the media to change the subject to “the issues” he cares about.

Each time, the Trump campaign has explicitly directed surrogates to defend Trump’s (increasingly indefensible) performance. It’s to the point where when Trump campaign manager Kellyanne Conway acknowledged that “we are behind” in an interview with NBC’s Chuck Todd on Sunday, it made news — because it represented a split with the boss.

As a result, some advisers have simply bailed out or distanced themselves from the candidate. Others have learned the rules: Repeat what Mr. Trump wants you to say, both to the public and to his face, and you’re good. Both Chris Christie and Rudy Giuliani were known as stubborn, irascible politicians before this year; both of them have shown impressive adaptability in parroting the Trump line, whatever that line may be.

Like many things about the Trump campaign, this tendency has gotten increasingly comical as Trump continues to sink in the polls. But unlike some things that make for badly run presidential campaigns, Trump’s sycophant problem is also a sign that he’d make a bad president. Arguably, it’s an even bigger one.

It’s amusing when Trump’s refusal to allow people to tell him what he doesn’t want to hear leads to him turning Texas into a swing state. It would be a lot less funny if he were president overseeing mass deportations, increased hate crimes, and a deteriorating relationship with Mexico — turning Texas into a war zone and refusing to hear any suggestion that he might change course.

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