I recently read Bertrand Russell’s The ABC of Relativity, his 1925 attempt to write a “popular” book on Einstein’s theories of special and general relativity. It’s notoriously difficult to non-mathematically conceptualize (let alone imagine) space-time in any clear way, but Russell did an admirable job of presenting the basics in relatively (excuse the pun) simple English, with a few geometrical constructions to help. Near the end he allows himself to philosophically muse a bit on the mathematical abstraction of such theories, and on how little – according to his view of science and reality at the time – they actually tell us of the “intrinsic nature” of matter and energy; here’s perhaps the best passage on this topic-
Between a piece of orchestral music as played, and the same piece of music as printed in the score, there is a certain resemblance, which may be described as a resemblance of structure. …when you know the rules, you can infer the music from the score or the score from the music. But suppose you had been stone-deaf from birth, but had lived among musical people. You could understand, if you had learned to speak and do lip-reading, that the musical scores represented something quite different from themselves in intrinsic quality, though similar in structure. The value of music would be completely unimaginable to you, but you could infer all its mathematical characteristics, since they are the same as those of the score. Now, our knowledge of nature is something like this. We can read the scores and infer just so much as our stone-deaf person could have about music. But we have not the advantages which that person derived from association with musical people. We cannot know whether the music associated with the scores is beautiful or hideous; perhaps, in the last analysis, we cannot be quite sure that the scores represent anything but themselves. But this is a doubt that the physicist, in a professional capacity, cannot entertain.
-Bertrand Russell, The ABC of Relativity (pp. 217-218)