The Einstein Approximation Sequel

Do you know that when you try to figure out something and therefore you can’t sleep? You always think about the same, the whole time, over and over again? Or you think about the dream you had the night before? Sometimes it is just a name or any sort of irrelevancy that don’t wanna come into your mind.

I had this not only once. I walked into my room, and before I did that, I knew exactly what I wanted to do, but in the room I had no clue. I thought and thought and thought but couldn’t remember. Or I made a crossword puzzle and the correct answer was on the tip of my tongue but I couldn’t say it. Do you know what I mean?  Or I tried to understand a simple equation like in maths. Or I wrote a word, the computer “said” it’s wrong and I looked and looked at it but couldn't find the mistake. And then someone came, and without thinking, solving the equation, writing the word correctly on which I was thinking about for such a long time. And he or she solved that in a blink of an eye and I thought: why haven't I figured it out?

I found this on the internet. When I read that kindergarten children can do this easily but a professor can’t, my first thought was that this is impossible. In fact, I have to say, I hadn’t figured it out when I first saw it. I thought about it, but couldn’t find the logic. Maybe we have learned too much, think too abstract, I don’t know. Here is it, maybe you find the right solution. Think about it and please write me your solution. I finally figured it out and so know its logic now ;)

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