When I first noticed this thread, I had a few quotes in mind to add to it. But after having read the quotes that have been posted here, it was obvious that those I had in mind were child's play to the solvers who can work these out. How do you even begin
to work some of these puzzles? I see now the reason for the 15 - 20% of puzzles that I fail to solve. Uff da.
Ben Franklin's quotes consistently give me fits. But, not to sell myself short, I have noticed that I am often able to solve quotes that have only a 15% or so solve rate, and that does boost my confidence.