Philosopher Nick Bostrom published a rather convincing argument in 2003 that we’re probably living in a computer simulation. Read it and you’ll understand why Elon Musk says, “The odds that we’re living in base reality is one in billions.”

In short the argument goes like this:

A lot of people think we’re on the brink of creating super powerful computers and A.I.

If we are, then we’ll soon have the ability to create vast simulations of reality, populated with simulated people who are conscious yet don’t know they are simulated.

If we can create real-world simulations, we probably will.

Scientists might run simulations of history with different variations to see how things play out. Gamers might do the same. Wealthy people might create fantasy worlds for themselves. If it’s cheap enough, many people might do it. Who knows? Conscious machines might do it to distract the humans whose bodies they are using to generate power. Whoever creates these simulations, it’s fair to assume they might create a lot.

Given that one base reality (the reality that developed this technology) would lead to countless simulated realities (populated, again, with conscious beings), then odds would be that we currently live in one of the simulated realities.

Yeah. "The Matrix Reloaded"

There are some ways around this conclusion, but they range from unnerving to unsatisfying.

On one hand, we might be overestimating the likelihood of mankind reaching that super computer-powered “posthuman” state.

If we are probably not on the brink of a computing breakthrough — either because the technology is unexpectedly complicated, or because we’ve underestimated the existential risks facing mankind — then the odds shift back in favor of us living in base reality. A naive, overoptimistic, and possibly doomed base reality.

Can we go back to the simulation?

Another argument against us living in a simulation is that, even if a posthuman state is likely, posthumans won’t have much interest in simulating reality.

Futurist and Age of Em author Robin Hanson made this case in a recent exchange with Inverse. “We are not actually very eager to simulate our past, except for the few parts of the past that have the most cultural resonance to us,” Hanson wrote. “Pick a person in the past, and we do almost nothing like simulating their world. Not in novels, in plays, in video games, nothing.”

But, uh, count us among the people who would eagerly create simulated realities to play around with — and if there are many people like us, and this technology is realistic, then yeah, we’re back to probably living in a video game.

Let's do this.

So what if we do live in a simulation? It might actually be a moot point, Bostrom argues. After all, the reality we live in appears to follow predictable rules, and our way of living and understanding the universe is built around those rules.

“Properly understood, therefore, the truth … should have no tendency to make us ‘go crazy’ or to prevent us from going about our business and making plans and predictions for tomorrow,” Bostrom writes.

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