A number of times when the Talmud is ping-ponging back-and-forth trying to
determine the underlying reason for a difference of opinion, it will state
that one of the parties learned a din from a particular textual source,
which the other party did not (lo mishma lei)
These seem to come in a number of different flavors such as a possible
extra letter (e.g. megillah 17b dvarim/hadvarim) or an extra word (eg bava
metzia 27b mimenu).
I was thinking that in other circumstances where such a letter or word
appeared, there is no debate, and the derivation is accepted by all.
I was wondering if anybody had seen anything which indicated that a
particular rabbi tended to (or not to) use such a source as a general rule
and/or is it possible that the decision as to whether to use or not you
such a rule was dependent on what that Rabbi already believed was the
pre-existing halacha that needed to be obtained?
KT
Joel Rich
This is ribui umi'ut, R Aqiva style derashah.
There are two schools of derashah: DeVei R' Aqiva and DeVei R Yishma'el.
And each wrote their own midrashei halakhah. More detail at
https://aspaqlaria.aishdas.org/2021/08/03/midrashei-halakhah-2
Rabbi Yishma'el's 13 rules are all about what phrases mean. He is the
one who says "dibera Torah belashon benei adam". Kelal uperat is about
whether a given text means something inclusive or more limited.
Meanwhile, R Aqiva's list of 19 rules are more about keywords -- "akh"
and "raq" are mi'utim. Even "es" became a ribui.
The double use of the shoresh in "aseir te'aseir" means something to
R Aqiva's school, whereas it's just how Hebrew works to R Yishma'el.
It's R Aqiva's school that produces mishnah -- R Aqiva, R Meir ("stam
mishnah keR Meir), to Rebbe. So although we talk about R Yishma'el's
rules in shacharis, it's R Aqiva's that end up having greater weight
in halakhah.
Also, with regard to gezeira shava, some held as long as the word is
noteworthy in one usage, there were grounds for a GS. Others required
it be derashah-worthy on both sides. Shemu'el didn't require anything
beyond common usage (i.e. even when the GS is einah mufnah kol iqar).
https://he.wikipedia.org/wiki/מופנה
In any case, it therefore often happens that their are derashos that
one tanna uses that doesn't exist for and therefore doesn't need to be
reused by his bar pelugta.
Tir'u baTov!
-Micha