My freshman year of high school I was going to a brand new school where I knew very few people. (I had been at a magnet school and this was my neighborhood feeder school.) So, when we were told to pick partners for math, I was really excited when a guy rushed over to me to be my partner. I thought: Yay! People wanted to be my friend! But then he turned to me and said, “You’re Jewish right? Jews are good with numbers.”
I was crushed. And, also, I am and was very good with numbers. But, apparently not all Jews are as we can see on the daf . . .
The Sages taught in a baraita (Tosefta, Ketubot 11:2): In a case of three experts who went down to assess a certain property in order to determine the amount to be collected from it for repayment of a debt, and one says it is worth one hundred dinars, and the other two say it is worth two hundred, or one says it is worth two hundred dinars and the other two say it is worth one hundred, the assessment of the single expert is nullified, since his is the minority opinion, and the assessment of the two others is accepted.
Okay. So, if 2 out of 3 say it’s worth a certain amount, we accept their ruling. Fine. But what if all 3 give different numbers?
If one says the property is worth one hundred dinars, and another says it is worth twenty sela, (= eighty dinars) and yet another says it is worth thirty sela (120 dinars), it is assessed at one hundred dinars, which is the average of the assessments, as it is equivalent to twenty-five sela.
Okay, so three judges assess and give three different numbers: 80, 100, and 120 we take the average = 100. Easy and good! But, or course, not all agree:
Rabbi Eliezer, son of Rabbi Tzadok, says: It is assessed at ninety dinars. Aḥerim say: An appraisal is performed of the sum between the two most extreme assessments and then divided by three. This sum is then added to the lowest assessment.
Oh good Lord.
Let’s keep those same numbers. According to Rabbi Eliezer, we would take the two lowest numbers, 80 and 100, and take their average = 90.
According to Aherim (judges in the Diaspora), we take the two extremes, 80 and 120, take the difference (120-80=40), and then divide by three (13.3333). Finally, we add this number to the lowest number = 93.3333.
But, the rabbis didn’t like math of those “Aherim”:
Rav Huna said: The halakha is in accordance with the judges of the Diaspora. Rav Ashi said: We do not even understand the reasoning of the judges of the Diaspora; shall we then establish the halakha in accordance with their opinion?
The math, just too hard. But, at least we can see why the diaspora are ruling the way they are – they are trying to factor in the opinions of all three judges and find a fair compromise.
But why would we only factor in the two lowest numbers? The least beneficial? There is a principal
There is a Talmudic idiom, Tafasta merube lo tafasta (Hebrew: תָּפַסְתָּ מְרֻבֶּה, לֹא תָּפַסְתָּ, “If you have seized a lot, you have not seized”). The idea is that when it is possible to take a particular law from two different sources, it should be taken from the narrower of the two, in order to stay on the safe side. It’s like the english expression “A bird in hand is worth two in the bush,” meaning it’s better to be content with what you have than to risk losing everything by seeking more.
The gem is two-fold. 1) Be grateful for what you have and don’t worry about those who have more. 2) To be a good Jew, you don’t have to be good at math, but you DO have to try and be a grateful person who tries to do good.