First off when I use the word probably I mean it in a mathematical sense.
So lets begin with A Thought Experiment:
The year is 2055. Computers are crazy fast. They are so fast in fact that we can finally run simulations that mimic reality to the minutest of details. One fine summer morning you get into one of the dumbest dumb accidents. A drone comes to your rescue, it does everything it can to delay your death. The drone picks up your half dead body and rushes you to the nearest hospital, but your fate is kinda like humpty dumpty and all the futuristic doctors and all the futuristic bots can’t put you back together. The doctor comes to you with a glum face and tells you, your injuries are beyond repair and you are going to die. But since you are in 2055 you have an option, an option to become immortal. Immortality!! Didn’t I just say you are going to die like a minute back and that no one could repair you, so what is the catch? The catch is that you lose your body, let me not beat around the bush anymore, your only chance to escape death is to upload your brain onto a computer.
You really don’t want to die, so you choose to go digital. Now that you are a brain on a computer what do you do. Well the first thing you do might be to satisfy all your desires. The only problem is that after a while gratifying those desires would cease to give you as much pleasure as they originally did. Now what do you do. Well as luck would have it there are a plethora of adventures at your disposal. You do all kinds of stuff with no fear of death. You climb mountains, you jump off of planes, you even jump off of dangerous cliffs. Unfortunately you get bored of this as well. You try your hand at a bunch of other things (it’s not like you are short on time or anything, you are immortal now). The only problem is that whatever you try you eventually get bored of it. Finally you have a eureka moment & you realize that the reason why you get bored in every simulation is because all the while, while you are in the simulation you know that you are just a brain on a computer and you remember all the things you did in your other simulation experiences. So you decide to give a new idea a try, you enter the simulation as a baby, with zero memories of your other simulation experiences and make yourself forget your true identity that you are a brain on a computer. So after spending a crazy amount of time in every imaginable simulation you finally end up in this simulation called earth. You are born in some random hospital. After a few years you start going to school and then college and you know the rest of the story.
The obvious question that stems from this thought experiment is: How do you know if you are really real or a simulation of reality? You cannot rely on your 5 senses to answer this question as they can quite easily be deceived, even with the technology that we have today, using something like the Oculus rift or HTC vive you can experience immersion. A phenomenon where you feel like you are in the game. But before we get into the reality vs simulation debate it is worth pondering about the implications of the answer.
What if you were living in a simulation, what aspect of your life will you change?
This idea is by no means new. Plato pondered over this idea way back in 400 BC. One of the most important hallmarks of philosophical thought is that you can’t take things on face value, you should always be willing to accept that there is more to the world then what meets the eye. Regardless of how preposterous the idea that we are living in a simulation may sound, probabilistically speaking the chances are way higher that we live in a simulation rather than reality.
The simulation argument (proposed by Prof Nick Bostrom) is as follows: "A technologically mature "posthuman" civilization would have enormous computing power. Based on this empirical fact, the simulation argument shows that at least one of the following propositions must be true:
For some reason human-level civilizations fail to reach a posthuman stage – in which case we are real and not a simulation
Posthuman stage civilizations have no interest in running ancestor simulations – in which case again we are real
Posthuman stage civilizations have an interest in running ancestor simulations – in which case in all likely hood we are simulations who are unaware of the fact that we are simulations
If you remember probability from high school you know that the probability for something is the number of favorable outcomes divided by the total number of outcomes. The number of favorable outcomes in the first two cases is a small finite number but the number of possible outcomes for the third case would tend to infinity (because of the possibility of nested simulations).