This is, I think, what the Yogacara means by the assertion that the world is mind-only (cittamatram lokam). It means that external and internal, before and after, heavy and light, pleasant and painful, moving and still are all ideas, or mental classifications. Their relation to the concrete world is the same as that of words. Thus the world that we know, when understood as the world as classified, is a product of the mind, and as the sound “water” is not actually water, the classified world is not the real world.
