>“earth” element pulled things towards the center of the universe

Actually, in a sense, that seems correct. I don't know much about this stuff, but it sounds like, if it wasn't the mysterious expanding force, all the matter might have a tendency of pulling each other back into the origin of the universe.

Sometimes I wonder how those ancient Greek philosophers predicted so many things. I guess we owe them a lot, and also the Renaissance people, who I heard saved many writings from those ancient times. The whole science sounds like built on them.