A sphere is the minimal area that surrounds a given volume. As such it is the form a drop of liquid takes on if there are no forces acting upon it. But is this because of gravity, or because of surface tension? I claim it is the latter, because at least in the case of soap bubbles, since they have hardly any mass, but easily take on their spherical shape.
It is probably a bit more complex, but the sphere is an elementary form, and so I have thus far not been able to make up my mind about a belief like the flat earth or hollow earth. I did at one time in my past writing career create a SciFi novel where a trip in the Hollow Earth was part of the story, but that is what it was at the time: a story.
Nowadays, I keep my distance from all competing world views, and claim I do not know what is the truth. I do however hope to live long enough to see that truth unveiled!
