Gravity couples to all forms of mass-energy regardless of charge, colour, or any other quantum number. This universality is a postulate in general relativity (the equivalence principle). Pentagon Physics proves it. Gravity arises from the trivial representation of the binary icosahedral group 2I — the representation in which every group element acts as the identity. A mode in the trivial representation couples to everything equally, by definition. Universality is not a postulate. It is a consequence of gravity arising from the representation where all symmetry operations are trivial.