Can the theory that everything that exists exists in time and space, which is

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Can the theory that everything that exists exists in time and space, which is materialism as I understand it, explain how things have motion as well? Motion is not itself a thing that can be located within time and space it is only the word that we apply to the effect of something changing position in a continuous manner. But if the only things which exists exists in time and space what is there to move the things that is in motion? Certainly not something else which is in time and space since that demands as well an explanation for it's movement.