In my opinion,
Science makes civilization work.
Art makes it interesting to live in.
A good civilization has a nice mixture of both and many things you see incorporate both.
Architechture is prime example. An ideal building or city is one that is both functional and beatiful. You don't a function eyesore isn't particulary great, nor is a beatiful thing that works horribly or not at all(assuming it's supposed to serve a function). A Gothic Cathedral has a lot of both in it.
Or more relevent to this crowd, the AR-15. It's functional(science) and yet, IMHO, it's a beautiful thing to look at(art).
The arts are more then pretty pictures. Music, Theater, TV, Movies(and I don't mean artsy movies that few people like), Writing(Prose and Poetry), painting, sculpture, photography, design, etc.
Of course, there's good art and there's bad art, though it's usually pretty subjective. It's not as logical(or logical at all) as engineering or a math problem where you can quantify whether it is right or wrong, but rather, does it fullfill the goal the artist was trying to achieve, do you like it or not, and why.