A layman's questions about universes

The reason it's an analogy is because you have to go from the ballon example, which is a 2d surface expanding in 3 dimensions, to our universe, proposed as a 3d hypersurface expanding in 4 dimensions.Since human beings can't really visualize that, we communicate it by analogy. So, we are on the hypersurface of an expanding hypersphere, like the 2d surface of the 3d balloon.

Didn't you ever play Asteroids, Buz? Didn't you ever notice how the game area was finite but unbounded, in other words, it was impossible to hit an edge that you couldn't go past?The game represented that space by having you leave the screen on one edge and come back in on the opposite one. That's what we're saying the universe is like - it's curved in higher dimensions in such a way that if you travel far enough in a straight line, you wind up back where you started.There's no need to call us idiots because this makes sense to us and not to you.