All We Really See

Now we can say that, save for light, non of us have ever seen anything, because light is the only thing that we are physically capable of seeing.

Consider this: So, you think you've seen your hands?

What doesn't happen: Your hands [one would hope] have never been inside your eyes. They have never directly stimulated the retina at the back of your eyeballs.

What does happen: You have only ever seen what light looks like after being knocked about by your hands. Everything you think you know about your hands, visually, is nothing more than your brains interpretation of the disturbance that your hands had left behind in the stream of light that eventually entered your eyes.