'3 Body Problem' ending: What does Dr Ye Wenjie's 'joke' about God really mean?

The issue with a show as mysterious as Netflix's 3 Body Problem is you want to know the answers now — and that feeling gets amplified with the knowledge we may have to wait another year to get them.

One of the biggest cliffhangers David Benioff, D.B. Weiss, and Alexander Woo's sci-fi epic leaves us on is actually a two-parter: What was the real meaning behind the "joke" told by Dr Ye Wenjie (Rosalind Chao) to Saul Durand (Jovan Adepo) on the park bench in Episode 7? And in what way could it help with Saul being made a "wallfacer" in the finale, one of three people tasked with plotting their own secret, internal scheme to best the approaching aliens?

We've poured over the clues to try and work it out. The first part of this article analyses the show itself, while the final part contains spoilers from Liu Cixin's Remembrance of Earth's Past novel trilogy, on which the show is based (we'll mark it with a spoiler warning in case you want to bow out then).

What's the "joke" that Dr Ye Wenjie tells Saul?

In episode 7, Wenjie is released from custody, exposed as the spiritual leader of the alien-worshipping Earth-Trisolaris Organization (ETO). Now that she knows the aliens she initially contacted all those years ago aren't coming to play nice, Wenjie contacts Saul and tells him a long, strange joke about Albert Einstein and God. Here's the joke, in full:

"So Einstein dies. He finds himself in heaven, and he has his violin. He's overjoyed. He loves his violin more than physics. Even more than women. He's excited to find out how well he can play in heaven. He imagines he'll be pretty damn good. So he starts tuning up, and the angels rush at him.

'What are you doing?' they say.

'I'm getting ready to play.'

'Don't do that. God won't like it. He's a saxophonist.'

So Einstein stops. He doesn't play. But it's difficult. He loves music. And there's actually not much to do in heaven. And sure enough, from high above, he hears the saxophone. He's playing 'Take the 'A' Train', do you know that one? Einstein knows it too. And he thinks, I'm going to do it. I'm going to play with him. We're going to sound great together. So he starts playing 'Take the 'A' Train'. The saxophone stops, and God appears. He marches over to Einstein and kicks him in the balls, which hurts, even in heaven. Then he smashes Einstein's beloved violin to bits. Eternity without music. Heaven has become hell for Einstein. And as he writhes on the ground, holding his smashed balls, an angel comes over and says: 'We warned you: Never play with God.'"

Not exactly a rib-tickler, is it? But the point of the joke clearly isn't to make Saul laugh. There's a hidden meaning in there. The question is, what?

What does Wenjie's joke mean?

Once Wenjie realises the aliens are now afraid of humanity and want to wipe us out, she clearly makes a plan.

"I'm an old woman, whose old beliefs have led us down this terrible path," she says in episode 6, addressing the aliens directly. "But I still have an idea or two left in me. And centuries from now there may well be a fair fight — or no fight at all."

The next time we see Wenjie in episode 7, shortly before she calls Saul to meet, she looks at two books (both of which are actual, real books): K.H. Erickson's Game Theory: A Simple Introduction, and Michael Bodin's Fermi's Paradox: Cosmology and Life. Aside from the joke itself, these books are the biggest clues we have as to what Wenjie might be trying to communicate to Saul. The first book on Game Theory is essentially a social science book about strategy, while the second book addresses the question of life in the universe. In short, Fermi's Paradox poses a simple question: If there are other species in the universe, why haven't we encountered them yet?

Hidden somewhere in Wenjie's joke, it would seem, is a strategy for either fighting the aliens, or avoiding a fight with them altogether. Could the God in Wenjie's joke be a metaphor for the aliens travelling across the universe to destroy us? If that's the case, maybe Einstein represents humanity. By playing music, he alerts God to his presence. Is the joke a warning for humans not to draw attention to themselves? But if that's the case, isn't it a bit too late for that?

Warning: The following section contains spoilers from Liu Cixin's novel trilogy. We've tried to keep them light, but they will likely spoil some elements of the show's future seasons.

What do Liu Cixin's books tell us?

For anyone who can't wait, the answer to the joke lies in Liu Cixin's second novel in the trilogy, titled The Dark Forest. The title itself actually forms part of the answer. "The Dark Forest" is essentially a possible solution to Fermi's Paradox, suggesting that the reason we haven't encountered other alien races is because the universe is like a forest at night — everyone stays silent in order to remain unnoticed. Alien races don't broadcast their locations because they don't want other races to detect them — and potentially attack them.

With this in mind, Wenjie's "joke" suddenly makes a lot more sense. Einstein playing the trumpet and incurring the wrath of God isn't a warning — it's the dark forest analogy in code. A social strategy answer to Fermi's Paradox, and possibly something Saul could use in his role as wall-facer.

How to watch: 3 Body Problem is now streaming on Netflix.