You know when people quest for "pure reason" by unreasonably disregarding everything their emotions consider unreasonable? You end up becoming a LessWrong cultist.

To start with, the sense of beauty is a natural thing we are born with. It's hard to say why, but there seems to be an innate association between goodness, health and beauty. When you go up to the mountains and just see nature in all its glory, or watch a sunset across the sea there is a sense of wonder. Add a cabin to the mountains, or a lone boat on the horizon, and that sense of wonder may even be enhanced. You might ask who is there, that appreciates nature so much that they can't watch it from far away, but need to be surrounded. Replace all the trees with apartments and fill the horizon with freight ships, is that wonder preserved?

Now, the interesting thing is that ideas can be beautiful. There is an aesthetic to mathematics, simple and symmetrical ideas are often the truest. There is an aesthetic to programming, which is the tool I use. Elegant algorithms can often solve problems with less code and fewer potential errors. In philosophy too, there can be beautiful ideas. There's a beauty in a phrases such as "do unto others as you would have them do unto you" or "from each according to his ability to each according to his need". Two morally opposite phrases both share this quality of beauty. Now, it becomes apparent that beauty and good have a dubious relationship. Why is that?

I'm speculating here, but I think that the difference is the relationship with reality. It is the act of constraining our creations, forcing them to conform to something, whether it's our sense of aesthetic or mathematical axioms, that imbues the beautiful with the good. Therefore, the good artist lets external beauty be a guide to his thinking. The bad artist tries to impose his internal reason on the outside world.

This interplay between beauty, goodness, and the mind and hand of a creator forms the basis of some kind of spirituality.