Now you are just using the Cartesian argument which I discussed in my other post. I thought that your 'trilemma argument' was a different argument from the classical argument from illusion (and by the way, you said previously you agreed with me that the argument is incoherent). — Fafner

It is incorrect, because I believe despite evidence that you are something even if I wasn't around. Of course, I believe I will die one day.
Now you take for granted that there is something. E.g. I exist :) But you have given no evidence. Further there is a problem with your notion of taking for granted. Let us say, I take for granted that there is a God. Now that is not evidence for a God, so why should the fact, that I take for granted that you exist, be evidence for your existence.
You still haven't given any evidence. It boils down to that I have no evidence, therefore you have evidence. Namely that when between P and non-P, non-P is wrong, then P is true. That is not how logic works.
You have made a naive realistic claim - "You know that you perceive something by perceiving it, how else?", but you have given no evidence.
#I know, that I perceive something by perceiving it.
#I know; that I don't perceive something by perceiving it, because I know, that I am a Boltzmann Brain.
#Either case is not knowledge.
You don't get the last one, do you?

To be an old school Skeptic means in some sense not to believe in knowledge, just like some people don't believe in the concept of a god/gods.
I use the word knowledge as an idea that some people believe in, but I don't believe in knowledge.
You don't seem to understand doubt.
I doubt that I am in the world, you know you are in.
I doubt that I am a Boltzmann Brain and I doubt that we are in a simulation.
But none of that is evidence for the fact that we have knowledge.