For our species, the idea of art as ornament is a relatively new one. Our ape brains got too big, too big for our heads, too big for our mothers to birth them. So we started keeping all our extra knowing in language, in art, in stories and books and songs. Art was a way of storing our brains in each other’s. It wasn’t until fairly recently in human history, when rich landowners wanted something pretty to look at in winter, that the idea of art-as-mere-ornament came around.