Reading a bio of Alan Turing : the Enigma (by Andrew Hodges). The guy who broke the Nazi code & invented your computer.
got me wonderin' about the likenesses between:
the "abba" rhyme scheme
John Irwin wrote about (some of) this with great erudition (The Mystery to a Solution : Poe, Borges and the analytic detective story).
So did Alastair Fowler, in his books on number symbolism & structure in Renaissance poetry.