I believe art to have a special cognitive role for men, which is a step quite far from the rather common notion of art having developed from “too much spare time” into something humans “just do,” without any role in their survival whatsoever.
back tens of thousands of years ago men begun to show signs of possessing a conceptual mind through decorating their artifacts with, mostly, geometrical patterns. this is not to say that animals don't have concepts, but only to show men to have complex concepts enough to have developed a will to externalize them, as if to really “see” what these concepts are. same works with something called “moral ideals.” we tend to have a hunch derived from a collection of previous life experiences of what is right and what is wrong, but to really make something out of that raw material of concepts and ideas we need artistic process to formulate a solid entity which embodies those concepts into something coherent in the material domain.