I never bothered to study art history or theory in any great depth. In fact my bachelors degree says 'Science'.
It seems to me that artists are never just artists though. Like Proteus, they change shapes and adapt, some almost constantly.
My own art, (it seems presumptuous to call it 'art' sometimes) changes with my mood, with what is happening in my life at the time, with my varying mastery over different mediums, with the books I read and the music I listen to.
I think all artists, professional or not (and I am not) are like this, 'protean'.
I used to think that this inconsistency was a failure on my part to conform to some kind of style, but I've decided that art has enough room to accommodate my fickle artistic nature. So hurrah for all those who, like me, create art that reflect the changing nature of human beings. Hurrah for The Protean Art Movement. Photographers, sculptors, painters, doodle artists scribbling in the margins of your notebooks... whatever. You're awesome.