[Avodah] Eilu va'eilu

[Avi Goldstein via Avodah]

It has always been my understanding that eilu va'eilu means that both (or
more than two) are, within the sphere of Torah, "true" as long as they
emanate from a valid drashah. As the Rambam writes in Hilchos Mamrim, Perek
2, a Sanhedrin can overturn the ruling of a previous Sanhedrin if that
ruling was made based on the yud gimmel middos or based on sevara.

The Rambam states that the new ruling becomes normative. So, for example,
if a Sanhedrin ruled that yeush shelo mida'as is yeush, that is now the
d'oraisa rule. If a later Sanhedrin overturns the ruling, then the new
ruling becomes normative.

Both, however, are "true," because the Torah has shivim panim; the Torah is
multifaceted and can countenance more than one truth.

The Rambam seems to hold that Moshe Rabbeinu was merely given the methods
by which to darshan; he was not given the various possible halachic
outcomes. The Ritva (Eruvin 13b) states that at Sinai, Moshe Rabbeinu was
shown 49 possibilities for each halachic situation. Either way, it is up to
klal Yisrael to determine what the halacha is, but all the possible
outcomes are divrei Elokim Chayim.

Avi Goldstein