Materialism: a theory that physical matter is the only or fundamental reality and that all being and processes and phenomena can be explained as manifestations or results of matter“Everything is matter.” Who says so? I, the subject. And if there were no subject who says so, there would be no one for whom matter matters, and therefore there would be no sense in saying that there is anything at all, because being and its meaning are not separable from each other. Nothingness of meaning means nothingness of being. So there is at least (1) the subject's (2) consciousness of (3) matter, instead of matter only. All three components are necessary to make a satisfactory ontological picture of reality.
That I, as the subject, could be somehow reducible to my objects, or that my consciousness of matter could be somehow reducible to what I am conscious of, is absurd.
Matter matters to me, but nothing matters to matter.
So by doing a simple phenomenological analysis of the being of matter we find that materialism is a self-contradictory position.