Why does the Gemara assume that pi=3?

See various meforshim, and Artscroll of course. The Gra also has a great vort on a possuk about the original "yam shel Shlomo".

Rounding down. Also, they didn't have calculators for the really complex computations.

[Off topic: While sitting in shul on Shabbat, I was trying to get my oldest son to figure out in his head if the yam shel shlomo could really hold the equivalent of 150 mikva'ot as the gemara says given the dimensions of a mikvah and the yam shel shlomo.]

They still were able to figure out it was 3.14-ish. The Greeks knew it; why didn't the Amoraim? [Stammaim? ]

Gabbe, to this day nobody knows the exact value of Pi, why do you expect more from the Amoraim?

I'm not talking about an exact value. The Greeks had it down to 7/22. We use 3.14 as a useful estimate. A tenth is a significant enough chunk that anyone doing some basic experimentation ---like Tosafos who obviously sat down with some string--- would notice it. Not to mention that the Yam Shel Shlomo's dimensions leave a discrepency of what, 14 amos? No one noticed that?

Isn't the question on Nach (sefer melachim) rather than on the gemara?

Well, obviously we must conclude that the circle as we know it only came into existence around Medieval times. Prior to that, circles were not perfectly round.

Did the hahamim do basic experimentation? Doubtlessly some examples can be adduced to prove they did, others that they didn't.

It's on both.




Well, if the broken record says that Chazal knew the "science of the day"...they should have known this too.

The Gra has a gematria on the word "v'kavoh" which appears in the possuk describing the dimensions of the pool - basically, the "hey" at the end of "kavoh" is a kri/ksiv, and the ratio of the 111/106 x 3 = very close to pi.

Shame Ravina and Rav Ashi didn't know this GRA...

Lav davka. But let's discuss more pressing issues, such as: is the earth flat or spherical?

I don't think the earth is flat. That's my vote.

Why should Chazal have known the "science of the day?" I've noticed that most, if not all, rabbanim of the early modern period didn't know the science of their day.

Yes but what did the Torah scholars of yore hold?

Ah, but that's 'cos of...of...quantum.



Define "flat".

Depends which.


Flat enough that gravity pulls down in infinite parallel forces rather than meeting at a point or other circumscribed area.


I don't know what Rashi thought - I don't know if Rashi knew the earth to be round.

Chazal's View of the World

http://www.aishdas.org/toratemet/en_shape.html