Brad Pitt made a rare late night appearance on Tuesday’s Late Show With Stephen Colbert, joining the host for another hilarious installment of his “Big Questions With Even Bigger Stars” segment.

After joking that he hadn’t “been out in a while,” Pitt laid back on the blanket with Colbert as they asked each other some of life’s deepest questions.

“Do you think mathematics are the underlying structure of the universe, or did we just invent it?” the actor pondered.

“I’m not sure if numbers are the underlying reality, but one thing is absolutely true: You’re a solid eight,” Colbert replied.

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When pressed on the less-than-perfect score, the late night host admitted, “I didn’t want to seem desperate.”

Pitt also poked fun at some of his most famous films as he and Colbert tried to make each other laugh with silly nicknames like “Colby Cheese” and “Brad-imir Pitt-en.”

“Do you think anyone can ever truly know themselves?” the host asked.

“Doesn’t matter,” Pitt replied. “In the end, turns out we were all Edward Norton the whole time.”

“Is it possible to describe infinity?” Colbert then pondered.

“Yes it is,” Pitt answered. “It’s one less than the number of Ocean’s sequels we’ll be making.”

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However, when it came time to debate time travel, Colbert hilariously used his hypothetical world-bending powers to plug the actor’s new movie, War Machine.

Then it was Pitt’s turn. “I’d definitely want to go to the past.”

“Oh right, so you could kill Hitler?” Colbert asked.

“Nah, I already did that in a movie,” the Inglourious Basterds star shrugged. “I’d want to go to the past...so I could change the scene to include another plug for my movie War Machine, appearing on Netflix.”

War Machine hits Netflix next Friday. See more about Pitt's transformation for the military flick in the video below!

WATCH: Brad Pitt Rocks Silver Fox Hair in First Trailer for Netflix's 'War Machine': Watch!