A week after vowing to boycott Fox News, Donald Trump was on the network’s signature “The O’Reilly Factor” on Tuesday (Sept. 29), getting a grilling from host Bill O’Reilly on whether he’ll have to adopt a more “mature” style.

Trump defended his tone in his campaign but also acknowledged that O’Reilly had been “fair.” Trump had complained aboutFox News’ coverage, as well as two commentators who were guests on O’Reilly’s show who had been critical of his campaign.

“You were very fair. You are always fair. Almost,” Trump said at the end of his interview with O’Reilly.

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In one portion of the interview, O’Reilly prefaced questions by asking him whether they were even fair to ask. For instance, he asked Trump whether it was a fair question to ask whether he will have to change his style to be “kinder and more mature.”

“I think it is fair, but I don’t think the word ‘mature’ is very appropriate,” Trump responded.

O’Reilly pointed to a clip of Trump in which he called rival Marco Rubioa “clown” and asked whether that was “presidential.”

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As he has before, Trump said he went on the attack only after being attacked. “I am a counter-puncher. He hit me all of a sudden,” Trump said, calling Rubio “unbelievably weak on immigration.”

O’Reilly also pointed to Trump’s high unfavorable ratings in the polls, but Trump said that he also has the highest favorable numbers and his negatives have been improving.

“I am actually a nice person. I try very hard to be a nice person,” Trump said.

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O’Reilly asked a number of policy questions, including one about the tax plan Trump unveiled on Monday. Trump says that his broad tax cuts will generate economic growth, but the Tax Foundation said that it would greatly increase the deficit by over $10 trillion.

O’Reilly said that he agreed that something had to be done to spur economic growth, but expressed some doubts that enough would be generated from Trump’s tax cuts to make up for a huge loss in revenue. “I don’t know if that is going to be enough to stop the debt from rising another five trillion dollars,” he said.

Asked what cuts to government spending he would make, Trump said that he would cut the Department of Education and “the department of environmental protection, where they are actually going around causing damage as opposed to saving” the environment.

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“We are actually saving tremendous amounts of money,” he said.

Trump said he saw “very little downside” to Russian leader Vladimir Putin sending military to fight ISIS in Syria. “If he wants to fight ISIS, let him fight ISIS. Why do we always have to keep doing everything?”

Posted by:Ted Johnson, Variety