[Avodah] Chazal are Infallible

[Micha Berger]

On Thu, September 14, 2006 10:44 am, Kohn, Shalom wrote:
: Let me just say that I commend the gemara in Sukka to the list's
: attention, and you will see that chazal, rashi and tosafot are
: struggling with the relationships in a way that an elementary school
: child today would not.  Further, the gemara reflects a desire for
: precision (to establish shiurim for a kosher sukkah) which is belied by
: the suggestion of our posters that the "rules" were only intended as
: approximations.

The shiur of a round Sukkah was given by R' Yochanan. They then had to
reverse-engineer the sevarah, as well as what R' Yochanan meant. Moreover,
they couldn't just use the geometry, they had to use geometry as per the din
for precision for sqrt(2) and pi.

I do not see the gemara struggling with the math, but with peshat in R'
Yochanan. And many math majors needed to sit down and pen and paper to follow
the shaqla vetarya.

: Why do we assume Chazal had a good "secular" education, and more
: particularly, since we are dealing with shiurim to be yotzeh according
: to halacha, why would chazal NOT be as precise as possible?  Again, see
: the gemara I cited.

Simply because a good poseiq does not voice an opinion without researching the
metzi'us. This is true today, and it is a safe assumption about Chazal. I'm
not saying that they deduced that pi is irrational from the Torah. Rather,
that no baal mesorah would have gone on record without knowing pi as well as
they could turn up with solid research.

IOW, since the Bavliim of their time knew Greek math, why assume any opinion
considered seriously enough to get into shas doesn't reflect hitting the local
experts and their libraries?

On Thu, September 14, 2006 5:11 pm, Zev Sero wrote:
:> Pi, sqrt(2), the number of days in a month or months in a year are all
:> irrational numbers. Meaning, there is no way to give an exact number, the
:> exact value requires an infinite number of digits....           Estimation
:> is the only possibility.

: The Rambam, in PhM to the mishna in Eruvin, gives exactly this
: explanation for why the mishna says pi is 3.  It's impossible to give
: the exact value, it has to be rounded *somewhere*, and Rebbi decided
: to round it to an integer....

I disagree that it was Rebbe, since Rebbe is too late. As already pointed out,
since 3 < pi, this opinion is lequlah. Eiruvin predates Rebbe, Rebbe lacks the
power to be makhshir an eiruv that was hithertofor pasul. Lo kol shekein
sukkah. The notion that 3 is "good enough" for pi must be therefore deOraisa.
(And by eiruv, ke'ein de'Oraisa tiqnu.)

(Which means that the yam shel Shlomo is a ra'ayah, not a maqor.)

: Unfortunately, it doesn't explain the gemara, but the Rambam wasn't
: commenting on that, so he doesn't have to deal with it.  Tosfos,
: which does have to deal with the gemara, notes the problem, and
: doesn't even offer an attempt at resolving it.

I do not know what you mean by "doesn't explain the gemara". Please elaborate.
The gemara, like the mishnah, works with the assumption that since we can't
get perfect precision, we have a de'Oraisa telling us what to use. Perhaps
it's one of the shurim given as halakhos leMoshe miSinai.

On Thu, September 14, 2006 5:35 pm, RCM "hankman" wrote:
: But for halachik purposes [three] is the correct value, not an
: approximation, just don't expect a real circle to close by use of this value).

Agreed. Rebbe isn't writing 3 as an estimate of the "real din". The real din
is to use an estimate of 3. Which Rebbe exactly described.

BTW, real circular sukkos, eiruvin or yamim aren't perfect circles anyway

-mi
http://www.aishdas.org/asp