"There's a one in billions chance that this is base reality."

He says that humans are basically some advanced version of The Sims.

Yes, that idea sounds pretty absurd.

But we shouldn't just write this off. People used to think the solar system worked like this. But almost 2000 years before Galileo proved it didn't,

Aristarchus of Samos posited the exact same, crazy idea. Reality is probably not as it seems.

Musk is echoing a paper on this theory by philosopher Nick Bostrom. His argument goes like this...

“40 years ago we had Pong, like two rectangles and a dot.”

30 years after Pong, we got The Sims.

“Now 40 years later, we have photorealistic 3D simulations with millions of people playing simultaneously and it's getting better every year.”

So let's go about 10,000 years into the future

It's possible that when we get there, civilization will be entirely gone because there is a ceiling to our advancement.

Maybe it's because of global warming — or self-replicating robots.

“...if civilization stops advancing, that may be due to some calamitous event that erases civilization.”

But another possibility is that if we keep advancing — and assuming everything in the physical world CAN be simulated —

eventually, we'll simulate ourselves.

Every synapse in entire human brain, for everyone on earth.

Getting enough computing power to run billions of ancestor simulations could be a problem.

But Bostrom thinks we'd send tiny, self-replicating robots to other planets, which would turn the planet into a huge computer.

And some of the simulations would start making their own simulations.

In this scenario, there are billions of universes that are indistinguishable from our own.

That means, chances are, we are in one of the simulated universes.

And given the other possibility — which is human civilization has an inevitable ceiling — Musk thinks we better HOPE that we're in a simulation.

“Either we're going to create simulations that are indistinguishable from reality, or civilization will to cease to exist. Those are the two options.”

There is one other —maybe future humans just don't want to run ancestor simulations.

Maybe they think it's unethical, because there is a tremendous amount of suffering in the world. And that suffering would still feel real to simulated humans.

Or maybe they have other priorities.

So to recap, there are three possibilities. 1. Humans go extinct before we're able to run a simulation this big.

2. Humans don't run simulations because it's wrong or boring.

Number three, we are living in a simulation.

Elon Musk thinks that there's only a tiny chance we are in scenario 1 or 2 –

The philosopher Nick Bostrom thinks it's more like a 20% chance that we're in a simulation.

But if you're not into futuristic predictions, Bostrom thinks the argument also provides other rewards.

He says, “It suggests naturalistic analogies to certain traditional religious conceptions.”

In other words, if we're living in a simulation, there is a higher-level being — but it's some version of us!

This leads to a rabbit hole of conversations, which is why Elon Musk has rules about when he can talk about this.

“It got to the point where every conversation was the A.I.-slash-simulation conversation and

and my brother and I finally agreed we would ban such conversations if we were ever in a hot tub.”