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Bostrom's Simulation Argument Explained
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The simulation argument sounds like science fiction but is carefully reasoned. The philosopher Nick Bostrom presented it in 2003. It leads to three possibilities, one of which must be true.
The three possibilities
First: civilizations die out before they build powerful computers. Then there are never many simulations.
Second: such civilizations have no interest in simulating conscious beings. Again, simulations stay rare.
Third: there are very many simulations. Then it would be likely that we live in one. The simulation theory section gives more context.
Why at least one must hold
The three statements cover every case. Either many simulations never happen, or they do and we are probably part of them. There is no logical escape.
That is what makes the argument so compelling. It forces a choice without dictating one.
Where the limits lie
The argument stands or falls with its assumptions. No one knows whether conscious beings can be simulated at all. The computing power needed is pure speculation too.
So the trilemma is not a proof but a thinking tool. It links philosophy with the idea of information as reality.
Frequently asked questions
Does the argument prove we are simulated?
No. It only shows at least one of three statements must be true. Which one cannot be derived from it.
What does the argument rest on?
It assumes advanced civilizations could create very many realistic simulations. That assumption is uncertain.
What exactly is a trilemma?
A trilemma sets out three statements, at least one of which must hold. In Bostrom's case the three possibilities together cover every conceivable case, leaving no logical way out.
Why is it called an argument and not a proof?
A common misconception is that the trilemma delivers a result. It only shows how the three statements are logically linked, but does not say which one is actually true.
When did Bostrom publish the argument?
Nick Bostrom presented his simulation argument in a scholarly paper in 2003. The underlying idea of an illusory world, however, is considerably older.
How likely does Bostrom say it is that we are simulated?
Bostrom gives no fixed number. He only argues that the probability would be high if the third possibility holds and there are very many simulations.
Sources and further reading
- Are You Living in a Computer Simulation? — Nick Bostrom
- The Simulation Argument — Scientific American
Update note (as of: 06/03/2026)
First publication of the Bostrom argument spoke.
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