I never claim to be a real deep thinker, or, for that matter an artistic person, but here are my thoughts on it.
Personally, I think it all boils down to emotion and the expression of that emotion. Humans are capable of feeling such a wide range of emotions, and to be honest, a lot of times we find ourselves struggling to express those emotions, and finding that words are restrictive at times. I myself have at times felt emotions that I am incapable of vocalizing, but if I pick up my guitar and start playing, they just seem to come out. Something about the feel and sound of music can conjure up feelings that words never could. It is the same with a painting, a book, it is just a lot easier to express some feelings through those types of outlets, especially if the individual is not that good at speaking to people.
Some people are also uncomfortable relating some things verbally in a conversation. They just don't feel comfortable. But they have no problem painting or writing, because somehow, it just feels different than talking.
At least that is the way I am.
I think another reason is people like to capture the wonder or feeling of a certain moment or place. By painting a picture of something that they have seen, that affected them in some way, maybe they can look at it later and get a glimpse of those feelings again.
I do think that it is inherent in our race to need to express ourselves. We are a very social species. So I think that we also need to be artistic to a certain extent, to be able to fully express and communicate our feelings.
Anyway, that is what I think. it's late, so I may not have articulated myself clearly, but I just wanted to put my two cents worth into the conversation. every once in awhile I feel the need to post something serious.

Go figure.
