Einstein writes as follows: There are the two concepts of space: (a) space as positional quality of the world of material objects; (b) space as container of all material objects. In case (a), space without a material object is inconceivable. In case (b), a material object can only be conceived as existing in space.
Einstein further explains like this: Newton's concept of absolute space as the independent cause of the inertial behavior of material bodies corresponds to (b). Leibniz and Huygens resisted to this concept, and the subsequent development supported their resistance, because the concept of the material object as the fundamental concept of physics was gradually replaced by that of the field. If the laws of this field are not dependent on a particular choice of coordinate system, then the introduction of an independent (absolute) space is no longer necessary. -- Einstein adds the words, "There is no space without a field." --
However, Jammer argues in chapter 6 of his book that the Leibniz-Huygens concept of space, called the theory of relational space, is no longer universally accepted, referring to the new version of relationism proposed by Reichenbach and Grünbaum. I would like to write about space again after reading Jammer's new chapter.
- M. Jammer, Einstein and Religion: Physics and Theology (Princeton University Press, 1999).
- A Scholarly Description of Einstein's Religious Philosophy (2001).
- M. Jammer, Concepts of Space: The History of Theories of Space in Physics 3rd enlarged edition (Dover, New York, 1993; 1st edition 1954, 2nd edition 1969, both by Harvard University Press, Cambridge, Massachusetts, 1954).