President Donald Trump’s lawyer Rudy Giuliani continued his tirade against the meaning of truth on Monday evening, after telling NBC’s Chuck Todd over the weekend that “truth isn’t truth.”

Suggesting that truth is “relative” and “not absolute,” Giuliani suggested the only way to prove if a certain conversation between Trump and former FBI Director James Comey about Michael Flynn took place is if there are recordings.

“One person says the Flynn conversation took place. The other person says the Flynn conversation didn’t take place. What’s the truth? You tell me you how you figure out the truth,” Guiliani said during an interview with Fox News on Monday evening.

“It either did or it didn’t,” Fox News Martha MacCallum shot back.

“But it’s like the tree falling in the forest. Did anybody hear it? I mean, how do we know what the truth is?” he questioned.

“In situations like this, the prosecutors, the truth is relative and it’s not absolute like some philosophical concept,” Giuliani continued. “Maybe, maybe through their prejudices the New York Times and Chuck Todd can figure out the truth that Comey is telling the truth, but I can’t. I believe the President is telling the truth.”

Giuliani and the rest of Trump’s legal team have been haggling with special counsel Robert Mueller for months over the terms of a potential presidential interview with Trump. Trump’s team wants Mueller to avoid questions about obstruction of justice, but Mueller’s team has insisted on asking those questions in writing, at the very least.

Trump himself has been publicly enthusiastic about meeting with Mueller’s team, but only because he reportedly thinks he can convince the special counsel that his campaign did not collude with Russia to meddle in the 2016 election.