The nature of the reality we live in is quite an interesting subject. There may well be many interpretations of how both life or well anything came to be and exist in this world. All the rules that this world seems to possess seems to have come from something.
One interesting hypothesis proposed by Nick Bostrom is that our reality can be simulated. The argument is that the rate of technological progress seems to have no end in sight and will always be improving and evolving with time. We can already simulate small worlds with very finite number of rules and interactions with video games and other computer simulations.
In any way, these are just hypothesis and are quite hard to really test and see if they are true.
- Physicists found that simulating a few hundred electrons (using one particular method) would require more atoms than there are in the (known) universe. This is a good argument that we cannot simulate our own universe precisely, but it says nothing about the underlying nature of reality.
- Consider if Pacman took some time to study physics. He analyses Ghost behaviour and realises it would take more than 255 levels worth of data to describe it. Pacman concludes that he must not be in a simulation, because clearly there are only 255 levels in the world.