Look at it this way Art
You are just an amoeba in a large sea.
Or a frog in a pond.
All you...I.....we know....... is the environment in which we live.
We cannot see past that, even with all our telescopes and microscopes, we may "see" things, but we do not "know" them. We are three dimensional creatures. We are not sure what really exists out in space, or in the deep bowels of the earth. All we have are clues.
And we're still not sure about physics, or time/space or dimensions yet. We aren't able to measure everything yet, so there is still much to learn.