Because of video games, whenever simulation theory is discussed, NPCs (non-player characters) regularly come up. In a game they are computer controlled characters, and do not exist outside of what is necessary to progress the game in real time. If, for example, you pay a NPC to construct a barn for you, typically the barn will just appear. All the NPC was needed for in game time was a conversation.

Simulation theory is taking off in the regular world, and calling someone a NPC is a very recent putdown. So it is perhaps a good time to consider whether (if we are living in a simulation)  there are NPCs.

I will ignore what non-NPCs are – they could be actual conscious beings playing a game, or simulations based on a real living being, or something in-between. For argument’s sake, when I mention a player, I mean you or me, as we experience life. Presumably NPCs are hard-wired to not participate in simulation theory discussions, so, presumably, you and I cannot be one.

Can you test for NPCs?

In a video game you cannot interview or run tests on a NPC, so this never comes up. But in a real world we can, and it would be strange and noticeable if certain people did not participate in studies that could out them.

We, collectively, regularly complete tests. Schools, driver’s licence, eyesight, medical and so on. So, unless you want to decree that all medical professionals are NPCs, then someone will have noticed if a NPC doesn’t have blood or a brain or whatever. Creating a perfect replica of a player physically takes a lot of processing power.

Possibly, given its intricacy, a NPC declines to have a brain scan. That could be an easter egg. Otherwise, in terms of processing, an NPC is physically identical, and all that could be different is their thoughts.

Difficulty hiding them – variety of actions + circumstances

An NPC with less processing power used on thoughts will be hard to find. Yes, they could be mentally deficient people, but what use would they serve a simulation? Any NPC in our simulation, to avoid being noticeably different, must have describable taste (at least in TV and pop music and fast food), desire to buy products and services, desire to travel (perhaps), fall in love (at least nominally), raise children, perform work (few of us are factory workers these days) and so on. That is a lot of functionality that is the same as a player’s.  Possibly, though, you could find people who are somehow limited in all of those aspects – generic people – who live in the suburbs I guess. But nobody has yet.

The other way of looking at this is, what does a player have or demonstrate that a NPC does not and cannot? I have previously suggested artistry and invention. Possibly even just having a questioning mind, and critical reasoning. But if that was the case, how much different – in processing power – would that be from a NPC? I am thinking not much, but it is hard to gauge considering we cannot create any of those with computers ourselves.

All the other animals, fraction of computing power needed

While arguably all animals are NPCs, they greatly outnumber us (many trillions of ants, for example) and that would mean that the fraction of computing power needed for players to not be NPCs is relatively very minor to what is required to run the whole planet.

Why even have them and not fewer people?

We would of course need to prove a need for NPCs. Why even have them instead of fewer people on Earth, all of whom are players?

So, your mission is to:

• Find provable, quantifiable things that NPCs cannot do
• Find a physical easter egg in NPCs – like a brain scan on someone unwilling
• Find a purpose for NPCs (like factory work) that a player cannot or would not do

The other question is, how many players are there? If it was only me, then this could very easily just be a game. No need for blood vessels in a NPC unless I personally need to witness it. If there are billions of players, why even have NPCs?

Personally, if I am to entertain the idea of NPCs then it can only work like this:

• Only players can create something new
• Only NPCs do the worst of jobs
• NPCs switch off when not needed to actually do something (when being told that they did it will suffice)
• A physical attempt to prove NPCs – like chopping off someone’s finger to see the blood – will be the only way to know. Anything digital or non-local can be faked.

Blood-letting is a bad example, unless all the criminals and soldiers of the world are players…