I consider myself a rational, logical person and have to confess to finding some (rather large) holes in my arguement. It was the catholic church that fostered the western tradition of complex choral music (and art). Without that there would have been no need for Monkdude to do what he did. So yes I agree, we do owe a debt of gratitude to the catholic church.
Like I said, religion makes good evolutionary sense.(as does violence)
I don't know enough about music history to go further. Is not his contribution just one in a sequence of many? Could not someone with a different outlook to you point to something else as a crucial moment? They didn't invent music out of thin air, and protestants and evangelists gave us gossple (sp) and the blues and mormons gave us The Osmonds..
And I think the Greeks and Romans (amongst others) would dispute your claim that the catholic church founded western civilisation. Lets see..philosophy, mathematics, writing, architecture,oratorion, rule of law.... (I'm going to get all Monty Python soon.)