how do I know that I am not the only real person surrounded by perfectly disguised zombies?

Answer 1

You can't.
However you might as well believe that they are real.
This i kind of a "Pascal`s wager" situation.[1]
You can believe that people are zombies[2], or that they are real.

If they are indeed zombies and you believe that they are zombies -- you are OK, there is nothing you can do.

If they are indeed zombies and you believe that they are real -- you loose little because you have to treat zombies as real people

If they are real and you believe they are real -- you live a normal life.

BUT if they are real but you believe that they are zombies you will live a truly horrific lie. You will mistreat people thinking that they are zombies, you will not know love or compassion. You will loose a lot.

So the risks of assuming people to be zombies is far greater then assuming them to be real. So you might as well assume that people are real.

Answer 2

you cannot know it, just as you can never know whether you are in a game where everyone else is an artificial game character or whether you are an alien.. although you can never answer this kind of questions, it is always fun to ask it to yourself :))

Answer 3

You need to stop watching horror movies and get more physical exercise. It is affecting your judgement.

Answer 4

wow. SOMEBODY needs to stop watching horror movies for a while. =/

Answer 5

You don't.
Don't go out after midnight tonight.

Answer 6

I love your avatar

Answer 7

I can assure you that I am human.

Answer 8

um, are they eating your brain?
if not, you are probably safe, probably.