'What does he mean when he says words': Watch John Oliver's searing takedown of Trump's lies

John Oliver’s Last Week Tonight returned Sunday night for its fourth season on HBO—the first episode to air with Donald Trump as the President of the United States. Oliver devotes a solid 24 minutes tackling the reality of a Trump administration. Or rather, the disconnect between reality and many of the president’s statements.

“We have a president capable of standing in the rain and saying it was a sunny day,” Oliver said, referring to Trump’s false claims that it didn’t rain during his inauguration on Jan. 20.

“Normally we like to focus this part of the show on complex, depressing policy issues…but unfortunately we can’t until we address something even bigger. The concept of reality itself. And that is because of this guy,” said Oliver, over a picture of Trump. “Since taking office around 412 years ago Trump has made it clear that reality is not important to him.”

Oliver goes on to bring up “four basic questions”: “How did we get a pathological liar in the White House? Where are his lies coming from? Why do so many people believe him? And what can we possibly do about it?”

The host points out that Trump has lied about everything from the crowd numbers and weather on Inauguration Day, to the current murder rate in the U.S., America’s GDP, to voter fraud—he even lied about being invited to be a guest on Last Week Tonight.

As Oliver himself says, calling Trump a liar is “not a fresh observation.” But the decisions made on the basis of those lies make them worth examining more closely.

“Trump was telling the truth about his solutions to the problems he was lying about,” says Oliver, referring to the Muslim ban and the wall on the Mexican border.