Parsle, Sage, Rosemary, Thyme, and My Johnny Was a Shoemaker

I was listening to Pandora when - well it sounded like Simon and Garfunkel's Parsley, Sage, Rosemary, and Thyme (actually "Scarborough Fair/Canticle"), but it turned out to be a medley from John Renbourn's "The Lady and the Unicorn" including "Scarborough Fair".

I embarrassed myself.  A mistake like that would have seemed a grievous error when I was younger.  It seemed important to know the provenance of songs when I was in college.  Dealing with folk tunes or the blues gave everyone an opportunity to look foolish.  Riffs and lyrics were stolen/borrowed promiscuously.  Someone could get all agitated to learn that their shining light, authentic blues man had stolen from Lightning Hopkins or Blind Lemon.  (It didn't help that there was a  Johnson and a Blind Lemon Jefferson.)  Most of us seemed to come to an accommodation with the realization that somethings would never be resolved.

I've gotten to the state where I'm grateful to remember that I've heard a song before, and upset that I can't remember where.