Daniel's Approved Riddles
Below is my list of approved riddles. I have spent days, months, and even years solving some of them. Not all riddles are worth spending a year of your life on - only the good ones. What makes a riddle good?
In my mind a good riddle is well-defined: the problem should be clear, and more importantly the space of possible solutions should be clear. Many riddles don’t meet this test, for example the classic “look in the mirror and see what you saw…” riddle. What a shame it would be to spend your time working on a riddle, only to later learn that there’s no good answer!
Of course you can’t tell if a riddle is good (and therefore whether it’s worth your time) unless you can trust the person giving you the riddle. Most of these riddles have come to me from a variety of trustworthy people - my sister, my grandfather, my friend Karen, and above all my friends Aharon and Dorit Hochbaum.
For that reason I’m not a very big fan of sharing riddles on the internet. Riddles are only really fun if you have a trusted source to consult. Someone who you can run your ideas by; someone who can say “you’re on the right track, and yes the answer really does exist, and yes it’s within your reach”.
And yet, I’d like to share my riddles on the internet! So here’s the plan: I’ll share these riddles here, but don’t do them alone! Please reach out to let me know if you’re working on one - I’d be happy to discuss it with you.
Lastly, you’ll notice that I don’t list answers. I would hate for you to look at the answer without solving the riddle first. There are only so many good riddles in the universe, and for each riddle you only get one shot; then the egg is broken forever.
All the approved riddles
Added 2024
- The Egg Drop Riddle
- The Two Doors Riddle
- The Obtuse Partitioning Riddle
- The Prisoners with Hats Riddle
- The Colorful Hats Riddle
- The Hotel Room Riddle
- The Fair Coin Toss Riddle
- The Coins on a Chessboard Riddle
Approved riddles by difficulty
"Mild” riddles
🌶️
- The Two Doors Riddle
- The Hotel Room Riddle
- TODO: three people with hats
- TODO: bar of gold for week / month’s supply
- TODO: monty hall
- TODO: rubik’s cube
”Medium” riddles
🌶️🌶️
- The Egg Drop Riddle
- The Fair Coin Toss Riddle
- TODO: burning rope riddles
- TODO: crossing a river with 1,2,7,14
- TODO: getting around the world from one airport
- TODO: 100 bags of gold with 100 pieces
- TODO: 9 students in a temple tedx
- TODO: 100 coins in a room, 10 are heads, get them into groups with even heads.
- TODO: 1000 bottles of wine, one is poisoned, find it with 10 rats
- TODO: 100 plane passengers
- TODO: 100 ants
- TODO: 75 meter rope 100 meter cliff
”Spicy” riddles
🌶️🌶️🌶️
- The Obtuse Partitioning Riddle
- The Prisoners with Hats Riddle
- TODO: 5 pirates and 100 coins
- TODO: alice and bob see 8 and 12 trees
- TODO: 100 people on an island with one or two dots
- TODO: 100 prisoners and lightbulb
- TODO: 12 weights, one is lighter or heavier
- TODO: passing five cards
”Extra Spicy” riddles
🌶️🌶️🌶️🌶️
- The Colorful Hats Riddle
- The Coins on a Chessboard Riddle
- TODO: three gods
- TODO: pie-cutting game
Unknown spiciness levels
I’m not sure about these ones cause I haven’t solved them!
- TODO: two number reveal game
Quandries
These ones don’t require an answer, they’re just weird and interesting to think about.
- TODO: The “two envelope” problem
- TODO: The surprise lion
- TODO: Newcomb’s paradox
Approved riddles by category
Logic riddles
- The Two Doors Riddle
- The Prisoners with Hats Riddle
- The Colorful Hats Riddle
- The Hotel Room Riddle
- The Coins on a Chessboard Riddle