Candle problem by psychologist Karl Duncker

The Candle Problem by Karl Duncker, 1945

You are in a room with a table pushed against the wall. On it is a box of thumbtacks, matches, and a candle. You must fix...

Three cups puzzle

There are 3 empty teacups on the table. Can you put 10 lumps of sugar in them so that there would be an odd...

Fire on Island

You are on an island, which is densely overgrown with dry grass and bushes. Suddenly you see that at the one end of the island...
Irina Popova. White herd. Enhancing creativity

Complete to the Whole

A farmer wants to divide his 17 horses among his three sons. According to farmer the oldest son should get half of the horses,the...
Napoleon's creative solution

Napoleon’s creative solution

In 1804, Napoleon Bonaparte desired to take the title of Emperor in order to possess a great Western empire, just as his idol Charles...
Gauss. German mathematician

The Story of Young Gauss

In the lesson of arithmetic, the teacher, who decided to do his own business, asked the students to compute the sum of all the...
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Do The Opposite

A duke was hunting in the forest with his men-at-arms and servants when he came across a tree. Upon it, archery targets were painted...

Ship Ladder Puzzle

A ship is at anchor. Over its side hangs a rope ladder with rungs a foot apart. The tide rises at the...
War elephants

Convert Harm Into Benefit – Timur’s decision

Turco-Mongol commander and conqueror Timur (Tamerlane, 1336-1405), invaded northern India, attacking the Delhi Sultanate. The battle between  Turco-Mongol conqueror and Indian forces took place in...
Ancient gold coin. Creative Puzzle

Egyptian coin. Mindfulness Challenge

An archeologist claims he found a Roman coin dated 46 B.C. in Egypt.  Note: Roman coins can really be found in Egypt How much should...
Goat and Wolf. Riddle

Wolf, Goat, and Cabbage Puzzle

A peasant has to cross a river with а wolf, a goat, and a cabbage. The boat can carry the peasant with only one...

Small coin in the bottle

A guy claims to do the following thing. He puts a coin in a glass bottle. Then, he shuts the mouth of the bottle...