The dumbest thing I remember is a line or two from the old TV series, All in the Family.
Archie and his son-in-law, Meathead, are having a conversation. They were at odds with each other most of the time and I don't remember the discussion. What does stick in my mind is that Meathead was putting on his shoes and socks. Suddenly Archie says, "That's not how you do it!" Meathead (Rob Reiner) had put on one sock and one shoe, leaving the other foot naked.
Archie continued: "A sock and a sock! A shoe and a shoe!" The younger guy couldn't believe it. Neither could I. But Archie thought he was doing it wrong.
So now on some mornings when nothing else is on my mind, I remember the line - a sock and a sock.
You can tell nothing was on my mind this morning.