Matrices don't have to be "some deep mysterious thing about nature" to be important in themselves and not just beause they are well-studied. They merely need t

Matrices don't have to be "some deep mysterious thing about nature" to be important in themselves and not just beause they are well-studied. They merely need to be deep. "Matrices" is just a word for "Linear operators over finite-dimensioned spaces". Linear stuff is important. Finite dimensional systems are imporant. And even infinite dimensional linear systems tend to have the same properties as finite dimensional ones. All of this makes matricies important in their own right.