In music, we would be without Bach's "St. Matthew Passion," Schubert's "Mass in G," Mozart's "Requiem," Vivaldi's "Gloria," Wagner's "Parzifal" and Handel's "Messiah." We'd have neither the musical compositions of John Tavener and Arvo Part nor the choral music of John Rutter. (For that matter, there wouldn't be many choirs.) Nor would we have gospel music.
It's doubtful that even most so-called religious wars have been primarily about religion, and that an entirely faithless society would be a utopia. But if we're supposed to "imagine" all the glorious things awaiting us if we'll just abandon belief in God, perhaps we should also consider for a few moments what would have been lost, or transformed beyond recognition, without religion. Some examples:
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