I'm sure back a few hundred years, sailors would have claimed that the other side of the ocean is the final frontier. Seems like just a way of looking at it to entice people into believing in a cause.
At the moment we are at a point in time where we cant see the end of space but there might be another "ocean" at the end, who knows!
Actually this is a common misconception. Educated people have known the earth was spherical since the birth of astronomy.