Does anyone know of a name attached to this problem-solving tactic? Jim Propp ---------- Forwarded message --------- From: David Will <daw5de@virginia.edu> Date: Tue, Jun 30, 2020 at 8:17 PM Subject: Question about the self-referential aptitude test To: <jamespropp@gmail.com> Dr. Propp: Good evening. I know I'm a bit late to the party, but I just wanted to say I'm a big fan of your self-referential aptitude test, which I just discovered today. In the instructions, you mentioned this idea that the foreknowledge of the puzzle having a unique solution can, in and of itself, be used as a clue when solving the puzzle. I enjoy Japanese-style puzzles, and I've previously encountered this same phenomenon in games such as slitherlink and masyu. I'm also a graduate student in mathematics at the University of Virginia, so I've been curious about this idea from a mathematical perspective. I was hoping you'd be able to answer a quick question. Do you know of a name for this phenomenon? I'm lacking in knowledge about game theory (is that even the right subject?), so I was unsuccessful in my searches online. I'd like to see if this phenomenon has been studied with any sort of rigor. In particular, I want to know if it would be possible to construct a puzzle that requires this logic in order to be solved (in some loose sense, ignoring brute-force guessing). Thank you for your time. I'd greatly appreciate it if you'd be willing to entertain my curiosity. Best, Andrew Will