In the final stages of writing up a combinatorial argument, no part of which is really deep, but which is giving me absolute fits, so this song is in my head. Penn and Teller! I forgot or perhaps never knew they were in this video.

Also: my 14-year-old daughter knows this song and reports “Everybody knows this song.” But she doesn’t know any other songs by Run-DMC. I’m not sure she knows any other ’80s hip hop at all. “It’s Tricky” wasn’t even Run-DMC’s biggest hit. It’s very mysterious, which pieces of the musical past survive into contemporary culture and which are forgotten.