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In this month's Nebula exclusive, big alien theory, we're asked at the reason alien civilizations might be rare is because most aliens are huge.

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There's a lot of discussion about if we are real or merely in someone's simulation or dream,

but what if we are real?

We just died centuries ago and keeping you resurrected over and over again. Some call it the simulation argument, some the simulation hypothesis, and it's a concept

that in many ways predates the computer age, but fundamentally comes down to asking if

we are living in a dream or computer program or fundamentally if we are real.

Today we'll be looking at the specific case of ancestor simulations and indeed this is the actual case for computer simulation discussion,

but that tends to get left out of most discussions.

And in my opinion is a lot of why the topic is both controversial

and confusing to folks. I want to start from the outset, since this topic tends to draw

some reckless talk and clickbait, that I'm not going to prove to you today that you

are or are not in a simulation. It is not something that you can easily prove either way.

And it is a real possibility, but nothing approaching a certainty or likelihood that we're

in a simulation.

We will want to explain why today and also how concepts like ancestor simulations are distinct

from classic notions of us living in a dream.

The basic notion is hard to credit anyone, and indeed the idea

where in a dream probably dates back to the dawn of humanity, or whenever the dreamer

started dreaming. However, it was philosopher Nick Bostrom who developed the formal

...