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Logic and Lateral Thinking

Picture of mouse in a cardboard maze. It has eaten its way through the walls directly to the cheese.Picture of a Maze with a line drawn directly from one side to the other with the word Parkour written underneathSometimes we assume too much when we think.  We place restrictions on our thinking that the ‘rules’ never made explicit.

The mouse in the illustration was under no obligation to follow the maze.  I also have a T-Shirt with the picture at right.  I guess free runners have the skills to leap over tall buildings and …


This page will be used for serious logic questions as well as the more light-hearted and lateral question as well.


Transferring Liquid Between Beakers

Two beakers with different coloured liquids in themYou have a beaker containing exactly 200 mL of pure water.  You have a second beaker containing exactly 200 mL of pure alcohol.

They can mix, but they are chemically different.

You take one teaspoonful of water and drop it in the beaker containing alcohol.  You now take one teaspoonful of the mixture and return it to the beaker of water.

Now, is there more alcohol in the water, or more water in the alcohol?

Answer: Answer to the liquid transfer puzzle.

The Local Barber

Young adult male getting hair cutIn a small country town everyone has regular haircuts.

All haircuts are carried out within the township.  Some people prefer always to cut their own hair.  The others always get the village barber to cut their hair.  The village barber also lives in the town.

Now, just to make the conditions perfectly clear ... no one, except the barber, ever cuts anyone else's hair. And none of the men who cut their own hair ever let the barber touch it.

Question: Who cuts the barber's hair?

Answer: Answer to the village barber question

I have been watching your “Integration technique” videos with high expectation and excitement. They never fail to give me a lot of joy and much pleasure. You must have been one hell of teacher at your time! … just continue making highly enjoyable and intellectually stimulating videos. … Unfortunately, what you learn at the university, you hardly ever see again in your office job. That is why I try to repeat some thing I learned: to enjoy it a bit more, to marvel upon beauty, and to keep my brain sharp. There is where your videos come in perfectly: interesting, amusing and thought provoking problems neatly presented. … You do your best to share your passion, knowledge and experience. The least I can do is to say an honest “Thank you!” As I said, your videos give me much pleasure. You may freely let other people know that. … Rest assured that I shall be watching your videos in the future. With joy and excitement. And I shall comment on them from time to time. You just continue making them.
Zoran V (in private correspondence via YouTube, quoted with permission)

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