Is Space Fundamental?

Most of the universe doesn't have any air, and it's pretty empty. Even more important is this sort of idea that maybe we don't need space at all. Is it at the foundation of reality? Or is it just something that fills up something else? You know, imagine what it would have been like to be a person ten thousand years ago. We're doing this all the time, left and right, without realizing it. So now we're asking a similar question about space. Are our assumptions about space valid? Can we break it apart? Do we even need it?"