“When a smaller box s is situated, relatively at rest, inside the hollow space of a larger box S, then the hollow space of s is a part of the hollow space of S, and the same “space”, which contains both of them, belongs to each of the boxes. When s is in motion with respect to S, however, the concept is less simple. One is then inclined to think that s encloses always the same space, but a variable part of the space S. It then becomes necessary to apportion to each box its particular space, not thought of as bounded, and to assume that these two spaces are in motion with respect to each other.”
With this description Einstein would chose to bind the space to the interior of the sphere as it moved. Natural Inclusion chooses to bind the space to the background, or universe, as the hollow sphere moves. Natural Inclusion uses the term omnispace to describe all of the space, around and through the sphere and any other forms.
- Einstein, A. (1954). Relativity. University Paper Back, London: Methuen & Co, p. 138.