# Is the Universe a Computer? There is a view that the universe is not simply a metaphor for a computer, but *is* a computer. And that is what reality really is. David Deutsch argues that this theory misses the point about the [Universality](Universality.md) of computation, which is the way that computation links with physics. Through the existence of a [Universal Computer](Universal%20Computer.md) we can simulate any physical object. If this computer were outside the universe it wouldn't be very remarkable. You can always imagine some kind of a computer with some kind of way of operating that can simulate any laws of physics no matter what they were. And so you lose the fact that our actual laws of physics are intimately connected with computation. What is the connection? It is not that there is a computer outside the universe. It is that we can make [Universal Computers](Universal%20Computer.md) inside the universe. That is a token of a computability of the laws of nature. It is the reason for the unreasonable effectiveness of mathematics in the natural sciences. It is the reason for the existence of life and the possibility of science. Those things are explained by the existence of computers in the universe, but wouldn't be explained if the universe was in a computer. We can then say [Information's](Information.md) existence is indeed fundamental, but it not fundamental in the [Reductionist](Reductionism.md) sense. It is fundamental in the sense that there is a law of nature that the universe is computable. Computers are emergent objects. There is no such thing as a computer at the subatomic level. Or if you did make a subatomic computer it wouldn't be universal, and therefore wouldn't be fundamental. --- Date: 20241220 Links to: Tags: References: * [David Deutsch - Is the Cosmos a Computer? - YouTube](https://www.youtube.com/watch?v=UohR3OXzXA8)