What is Beauty?

How important is beauty? I don't mean prettiness. What I have in mind might best be described as aesthetically pleasing, which can include things that are quite stark and things that aren't visual at all but theoretical or behavioral.

I've heard that some Native Americans have a saying, "Walk in beauty." I understand it to mean something much more than just the typical idea of beauty. Something more like harmony with the natural order or the Tao or something like that.

How much is our need for order really a need for beauty?

One def. of aesthetics is: Of or concerning the appreciation of beauty or good taste. Is morality really just a need for what's aesthetically pleasing/beautiful?

Is the need for beauty instinctual? Do we as a species find beautiful what helps us survive?

How much is our spiritual path really a search for beauty?