three things i learned in school that i will never forget

Here are three things that I learned in school and will never forget.

A Talmudic Principle:
"אין רצוני שיהי פקדוני ביד אחר" It's pronounced "Ain r'tzoni sh'y'hey pikdoni b'yad acher." Literally
translated, it means "I didn't want my property to be in someone else's hand. This was a sentence from eight grade Talmud class. I don't remember which book of the Talmud we were in. The topic was who is responsible if a person's property is damaged while being held by a second person. Say, for example, I have your bicycle and it is damaged or lost. Do I have to pay you for the loss? The answer, of course, depends primarily on two questions:

• Why am I in possession of your property? Did you lend it to me to use? If so, am I paying for its use? Or am I  holding it because you need someone to take care of it? If so, are you paying me for the service?
• How did the object get damaged or lost? Was I careless? Was it normal use? Did I lend it to a third party?

That last question is where the concept (quoted above in Hebrew) comes into play. Unless I got your permission to pass on your property to the third party, the rules are very much against me.

Why do I remember this one concept when I don;t remember any other line of Talmud? Because our teacher, Rabbi Atik, insisted that it's really important. SO he got the whole class to chant it over and over again. Then, while we were still chanting, he stood us up and marched us up and down the hallway, into every classroom.

The Central Bank of the Soviet Union
It was the "Gosbank." In college, I took summer classes. One summer I took an economics class in money and banking. One question on the final asked for the name of the central bank of the Soviet Union. I didn't know, so I took a wild guess. "First Commie Savings and Loan" I wrote. I got it wrong, but the professor told me the answer. Had I remembered the answer from studying the text, I probably would have forgotten it by now. But in the event, I will always remember.

A cool fact about circles

Suppose you have two circles. One is inside the other, but they share one point. Now, consider a
string of circles in the space between these two circles. The circles in the string touch each other, and also touch the two main circles. The points where the little circles meet are all contained on yet another circle.

I remember this because of the complex analysis course I took in my second semester of grad school. The last question on the midterm (or was it the final?) asked us to prove this. As the professor was handing out the test papers, I saw the diagram on the last page, It looked complicated and scary. I went into a panic and started saying "Oh shit! Oh shit! Oh shit!" over and over. At some point I looked up and saw that the professor had stopped handing out papers and was staring at me. To this day I don't know if he was annoyed or amused.

The irony is that that question is the only one that I got completely right. It was a simple construction using linear fractional transformations.