Philosophers as far back as Plato millennia ago speculated that what we see may not be real at all.

Every night, most of us enter a dream-state where the physical laws of the universe are completely suspended, and we have little to no idea what this means.

Many people do not think dreams are worth looking into. But in dreams, such as in life, it all matters, or none of it matters. Would a simulation be much different from a dream?

Once upon a time, I dreamt I was a butterfly, fluttering hither and thither, to all intents and purposes a butterfly.

I was conscious only of my happiness as a butterfly, unaware that I was myself.

Soon I awaked, and there I was, veritably myself again.

Now I do not know whether I was then a man dreaming I was a butterfly, or whether I am now a butterfly, dreaming I am a man.

Zhuangzi

When it comes to evidence of living in a simulation, the mathematical nature of our universe itself is the best choice. The universe is broken up into pieces (subatomic particles) like pixels in a video game.

The laws of physics are computable and they have definite parameters. That means that they can be simulated.

Prestigious philosophers, reputed physicists and millionaire technologists are considering the possibility that we and our World might not be real, but only part of a video game.

An enormously sophisticated simulation: the Second Life or The Sims of the future.