Already in ancient times philosophers imagined that there is no way of telling that the world around us is real or that other people have a mind of their own. Perhaps I am the only one who is real while the rest of the world is my imagination. This could all be a dream. Some major religions claim that gods created this universe and that we are like them. In the Bible it is written that God said: “Let us make mankind in our image, in our likeness.”
For long it was impossible to clarify why this world might not be real or how the gods might have created it. Recent advances in information technology have changed that. This universe could be a virtual reality. We are inclined to think that what our senses register is real, so we tend to ignore evidence to the contrary. For instance, you may think you see a pipe when watching an image of a pipe.The caption of the famous painting named The Treachery of Images of René Magritte makes you notice: this is not a pipe.
In 1977 science fiction writer Philip K. Dick was the first to claim that we do exist in a computer-generated reality. This is the simulation hypothesis. He came to this insight after experiencing a psychosis. If he is right then his name suggests that our creators do like to joke around. Professor Nick Bostrom explored the probability the simulation hypothesis being true in the simulation argument.
According to Bostrom there could be many different human civilisations. The humans in those civilisations may at some point enhance themselves with bio-technology and information technology, live very long and acquire capabilities ordinary humans don’t have. For that reason these beings aren’t humans anymore and called post-humans. These post-humans might be brains-in-vats or have uploaded their consciousness into a computer and have no physical body. These post-humans may run simulations of their human ancestor civilisations. In that case we may be living in one of those simulations ourselves. Bostrom argues that at least one of the following must be true:
- Nearly all real human civilisations end before enter the post-human stage.
- In any post-human civilisation only an extremely small number of individuals are interested in running simulations of a human ancestor civilisations.
- We almost are certainly living inside a computer simulation.1
It comes with the following assumptions that appear realistic to many experts in the relevant fields, but are not provenbecause we have not managed to do it yet:
- The available computing power in post-human civilisations is sufficient to run a very large number of simulations of human ancestor civilisations.
- The human consciousness needs not to reside in a biological organism, but can be implemented in a computer, perhaps in a limited form that appears realistic.1
Bostrom then concludes that if you believe that our civilisation will one day become post-human and will run a large number of human ancestor civilisations then you must believe we are currently living inside such a simulation.1 It might be explained like this. We do not know at what point in time we are, before or after the invention of virtual reality universes. If every year has an equal probability of this technology being invented, and we are going to invent it in the next 10, 100 or 1,000 years, then it will not happen later than that, because by then we will have done it. But what are the odds of it happening in the next 10, 100 or 1,000 years compared to the billions of years that already have passed?
There are many uncertainties. The available computing power of post-human civilisations might not be sufficient. It is possible that nearly all civilisations die out before becoming able to build simulations of human civilisations. Maybe post-humans will differ from us to the point that they will not be interested in running these simulations. Bostrom doesn’t try to guess the likelihood of the options. He thinks that we have no information as to whether this universe is real or not. But that may not be true.
Featured image: The Treachery of Images. René Magritte (1928). [copyright info]
1. Are You Living In a Computer Simulation? Nick Bostrom (2003). Philosophical Quarterly (2003) Vol. 53, No. 211, pp. 243-255.