HEMPSTEAD, N.Y. ― A number of fairly mendacious statements were made during Monday night’s first presidential debate. But arguably the most brazen involved Donald Trump’s views on climate change.

The GOP nominee was called to task for claiming that climate change is a hoax perpetrated by the Chinese government. In response, he completely denied ever saying that.

Rarely are there moments when you can definitively state, with zero reservation, that a presidential candidate is lying. But this was one of them. Trump literally tweeted the exact sentiment he denied ever saying. Here’s the 2012 proof:

The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive. — Donald J. Trump (@realDonaldTrump) November 6, 2012

How can someone deny having said something with such conviction when there is readily available evidence that he did? This is the question The Huffington Post posed to several of Trump’s surrogates after the debate ended Monday night. Here are their explanations.

Rep. Marsha Blackburn (R-Tenn.)

HUFFPOST: During the debate Donald Trump definitively said that he never once said that climate change is a hoax perpetrated by the Chinese. But here is a tweet where he says just that. [We attempt to show her the tweet.]

BLACKBURN: Well, I don’t have my glasses on.

HP: Come on! OK, I’ll read it. [We read it.]

BLACKBURN: Well, many times when we talk about issues related to the climate, y’all have countries that would not be forced to come into compliance with some of these agreements. Then they will say they don’t have to abide by that, they plan to buy more coal.

HP: Do you believe that climate change is a hoax?

BLACKBURN: I do not believe in climate change. I think the Earth is in a cooling trend. It is not in a warming trend.

HP: You currently think the Earth is in a cooling trend?

BLACKBURN: It is in a cooling trend. It has cooled for about the past 10 years. And the thing that is so interesting is that when you say global warming or climate change, the climate will change. So yes, in that, I agree that it does. You have to ask, “Is it cyclical?”

HP: You know we’ve had about nine of the hottest years in the history of the planet have been in the past 10 years?

BLACKBURN: We have also seen the past 10 years a little bit of a cooling.

Note: The idea that the Earth is cooling is wrong.

Trump aide Sarah Huckabee

HP: [Reads her Trump’s tweet.]

HUCKABEE: I think what he said was, he didn’t think global warming was the number one threat to the world.

HP: He said, “I never said that.”

HUCKABEE: I’m sorry. I stepped out a couple times. I really don’t know what you’re talking about on that. The only global warming comment I heard was there at the end.

HP: Does he still believe global warming is a hoax? You’re a surrogate, you’ve got to represent him.

HUCKABEE: I’m not him. I’m his surrogate.

Republican National Committee senior strategist Sean Spicer

HP: How does he say he never said climate change is a hoax perpetrated by the Chinese when there is this tweet?

SPICER: I didn’t follow that. I didn’t hear what actually happened.

HP: Does he still believe what he put in this tweet?

SPICER: I don’t know. You have to ask him.

Sen. David Purdue (R-Ga.)

HP: How do you square the statement from the debate with this tweet?

PURDUE: You’ll have to ask him that. What he is really talking about is how unrealistic her expectation of switching to global green energy overnight is.

HP: But as a surrogate for the campaign, is the campaign’s position that climate change is a hoax?

PURDUE: Well, talk to the campaign

HP: You’re with the campaign.

PURDUE: I understand that. Right now, it is not proven. There are controversies about that. There are experts on both sides that will take opposing views on that. And for us to take the entire direction of our country and sacrifice our economy and put millions of people out of work because of something that they, the Democrats, are perpetrating, I find really irresponsible.

Note: The vast majority of scientific experts believe that climate change is real and that human activity is contributing to it.

Sen. Jeff Sessions (R-Ala.)

HP: What do you make of him saying he never said that and the existence of this tweet?

SESSIONS: I’m not sure what he had in his mind when he said what he said. He has not been saying that recently. He has been respectful of it, but he does believe in all energy sources and many of those are CO2-producing energy sources.

HP: Is it the campaign’s belief that climate change is a hoax?

SESSIONS: Well, I’m going to tell you what I believe.

HP: But you’re here on the campaign’s behalf.

SESSIONS: I believe that we don’t need to be spending, making the taxpayers pay, much more money for their electricity from solar cells.

HP: But is it the campaign’s position that climate change is a hoax?

SESSIONS: No. I don’t think it is a hoax. What I say is climate change, the explanation the scientists gave for climate change, made some sense: that CO2 could be a greenhouse effect in causing the temperature to increase. However, 15 to 18 years have gone by and we haven’t seen anything like the predictions come true that they predicted.

Campaign manager Kellyanne Conway

HP: He said that he never once said that climate change was a hoax perpetrated by the Chinese. There is actually a tweet about him saying exactly that. How do you square those two?

CONWAY: Right, so we are going to be quoting tweets? She voted for the Iraq War, but we’re asking him if he supported [it]. She proudly went down to the well of the Senate and voted for the Iraq War, yay!

HP: She’s not saying she never voted for the Iraq War. She in fact apologized for that ...

CONWAY: ... and nobody is asking her ... No, she didn’t. Listen, she’s been an interventionist hawk her entire career.

HP: Can you address the tweet though? Does he believe climate change is a hoax perpetrated by the Chinese?

CONWAY: What he has said is, he believes [climate change] is naturally occurring and is not all man-made. I’ve heard him say that. He’s also said that there are passionate views on both sides of the issue.

Editor’s note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims — 1.6 billion members of an entire religion — from entering the U.S.