...because the “tune” was almost entirely lifted from a Reformation-era German hymn by Hans Leo Hassler.

I'd love to hear more about that "lifting!"

Tunes are international. And this one is an American Tune.

are we talking about "O Sacred Head Now Wounded?"

Went in and played a bit with the piano and yes, I can "hear" it.

You know, kinda' like George Harrison's "My Sweet Lord" and the Chiffons' "He's So Fine."

Had never made the connection with the Simon tune before - and I "can" hear similarities, but, there's only 12 notes to chose from in Western Civilization music, so sooner or later, well, stuff happens!

And, gotta' say, ALL 4 examples are classics!

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my #1 favorite Paul Simon tune - well, at least until I listen to another one of his tunes!

This is a great version/recording. I'm partial to the recording from the Concert in Central Park, but..............