The Magic of Logic (4)

Entertain your kids with this kind of diversion. They will love it!

Yesterday I completed my second course in logic for talented students of a local school. They were ten to thirteen years old and after the final class had to give an evaluation. The result was hardly surprising: I had been able to feel it during classes. The students were delighted and urged the school to force me to do a continuation next year. None had switched off during the lessons, all 14 had worked hard on every problem I gave them, never losing attention or showing signs of boredom. Let me say this: it was not due to some superb skill that I possess, as an educator, it was the subject matter and the thinking process that captivated them.

Kids basically love to think. It gives them unusual pleasure to work on logical problems. The brain produces dopamine when they think hard, and that gives a pleasurable feeling. I will research this theory further, but I think solving these problems somehow produces a “high” which they continue to seek. They are always ready for more.

As I have described in previous articles (see links at the bottom of this page) I started my grand-kids on logical puzzles when the older of the two boys, Enders, turned six. He is now seven and has developed an ability to solve logical puzzles at least as well as most adults. I have tried them on his brother Hennes, currently six. He is becoming equally adept, and enjoying the puzzles just like Enders has, for over a year now.

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I want to give you an example, one that you can try on your kids. In the above picture Enders, has just turned seven, while Hennes is still five years old. On the table are three marking dots, two red and one blue. The kids are waiting for the puzzle.

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For this they had to close their eyes and I stuck a red dot on each forehead. I also concealed the blue dot. Now they could open their eyes and had the task of deducing the colour of the dot on their forehead.

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Enders and Hennes spent the first minute trying to squint up and see their own dot. But they couldn’t. Hennes wanted to rush to a mirror, but of course that was not allowed. He even tried to see a reflection on the table.

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Okay, guys, tell me the colour of your dot. After a minute or so Hennes said: “Mine’s blue!” I asked him how he knew, but he could not explain. “You are guessing!” I said, and he admitted that is what he had done. What else?

During this interaction I could see Enders thinking. And suddenly he burst out: “Mine is red!” — “Are you also guessing, Enders?” No, he was positive his must be red. I asked him to explain. You can watch him doing it (in German) in this video clip. What Enders says is: “If my dot were blue, Hennes would never have guessed that his was blue, since there was only one blue dot. So mine must be red!”

We all clapped at this perfect solution. But I had one more question for Enders: “If Hennes had not tried to guess the colour of his dot, if he had said nothing, could you have told me the colour of your dot?” — “No, of course not,” Enders replied, “then it would have been impossible for me to tell.”

I left it at that, and the kids went on to play their regular boisterous games. But suddenly, in the middle of jumping and pushing, Enders suddenly stopped in his tracks and came running over to me. “Even if Hennes had said nothing I would have been able to tell you the colour of my dot!” he said, full of excitement. How that? “If Hennes had seen a blue dot he would have immediately known that his had to be red, because there was only one blue dot. But if he says nothing, if he can’t figure it out, that means mine must be red!” There was great pleasure and pride on his face and voice.

A lady friend who saw this all transpire said to me: “This kid is a [expletive] genius!” No, he is just very smart. I called Enders and asked him about this. He put it correctly: “I am very good at solving puzzles. That is because my grandpa has been giving them to me for a year now.”

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Frederic Alois Friedel, born in 1945, science journalist, co-founder of ChessBase, studied Philosophy and Linguistics at the University of Hamburg and Oxford.

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