I was thinking about the analogy of an observer living in a two dimensional world. So as it goes, this observer would see a 3d sphere as a 2d circle. As the 3d sphere moves through the dimension the observer cannot see, the circle would seem to appear on his plane from nowhere, grow to the diameter of the sphere, and then shrink back to nothingness. Now we use this same concept using an observer in 3 dimensions, observing a 4 dimensional object moving through. Shouldn’t the observer see a 3 dimensional object appear out of nowhere, grow, and then disappear? If there were a fourth dimension wouldn’t we see this all the time? Maybe it's the case where things in four dimensional space never cross the 4th dimension coordinate we are locked into? Sorry if this is a stupid question. I’m a layman who keeps himself up all night pondering these things.