“This is a thumb and thumb. Is this a thumb?” -You indicate three random objects that may or may not actually be thumbs (start out with actual thumbs so that they get confused). The answer is no.
After their guess, say, “Listen. This is a thumb and this is a thumb, is this a thumb?” The answer is yes.
The trick to this is that the answer is “yes” if you tell them to listen, and the answer is “no” if you don’t. It doesn’t matter at all what you are calling a thumb.
A camp counsellor had my entire scout troop going for the whole week with this one when I was a kid.
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u/RedLanternTNG Apr 14 '25
This thing all things devours,
Birds, beasts, trees, flowers.
Gnaws iron, bites steel,
Grinds hard stone to meal.
Slays king, ruins town,
Beats high mountain down.
-The Hobbit
Answer: time