[twiceaday]

If you are an agent in a physical reality you need an internal model of that physical reality to have mastery over it; a way to simulate actions and outcomes with reasonable precision. There are infinitely many such models. Humans are born with one such model. It is our firmware. It was found via evolution and we all share the same one. You were not born as a blank slate, quite the opposite. What is the relationship between reality and a model of reality? What if every agent you could communicate with had exactly the same model as you? It would be easy to get confused and imagine there is no model at all; that you all are somehow experiencing the world as it truly is. We are all in the same Matrix. In order to explain the redness of red you must first explain the relevant aspects of redness in the specific model of physical reality that all humans share. We did not come up with the model. We inherited it at birth. We have no idea how it works. The only thing we can do is say "if you find yourself in the Matrix, look at something red, you will understand as we have understood, we do not yet know of another way."