Originally posted by Kid Vicious I barely know any theory and I learn most songs by ear anyway. I just know my way around the fingerboard fairly well. I mean, look at Billy Sheehan. He shreds on bass, but will openly admit he doesn't know {censored} about the theory behind the stuff he plays.
Learning theory is not that hard, and it really speeds up the learning process in terms of understanding how and why it works, instead just going "Umm, yeah I play it like this". Also, Ignorance to theory doesn't earn you much respect around other players.
I'm not saying you have to learn theory to become a good player, but it sure helps to have a clear understanding of the scientific side of the art.