An excerpt from Rabbi Herschel Schachter:
The Talmud, as well as later rabbinical literature, is replete with halachic disputes. The halacha has had to decide which opinion should be followed. Should we assume that the rejected view was mistaken and simply incorrect? The Gemara (Eruvin 13b) states regarding the many disputes between Beis Shamai and Beis Hillel that, “eilu v’eilu divrei Elokim Chaim – both opinions are the words of the Living G-d.” although in the overwhelming majority of cases we have not accepted the views of Beis Shamai, this does not mean that they were wrong; one who spends time learning the views of Beis Shamai is in fulfillment of the mitzvah of Talmud Torah. Beis Shamai were also basing their opinions on middos she’ha’Torah nidreshes bohein; they were following the principles and the rules of the Torah She’b’al Peh, just that they came to a different conclusion than Beis Hillel. Therefore learning their opinions would also constitute a proper fulfillment of the mitzvah of Talmud Torah. To use the terminology of Rav Soloveitchik, their views also constitute a cheftza shel Torah.
The Ritva (ibid) explains as follows: when Moshe Rabbeinu was on Har Sinai and received the Torah from Hashem, he asked the Ribbono Shel Olam what the din would be in various cases, and in some Hashem told him the din is assur, in some He told Moshe muttar, and in some Hashem told him that the case had elements of issur and elements of hetter and He leaves the matter up to the Torah scholars of each generation to determine whether – according to their perspective – the elements of issur outweigh the elements of hetter, or the reverse; and since different people can each have different perspectives even though they are looking at the same thing, more than one can be correct. This is the meaning of the idea that, “eilu v’eilu divrei Elokim Chaim.”
This concept does not always apply in all cases. Rashi and Tosafos (Kesubos 57a) point out that sometimes we must assume that one of the opinions is clearly incorrect. Sometimes we see a dispute among the later rabbinic authorities where one of the opinions simply overlooked a passage in the Talmud, or sometimes even an explicit passuk in the Chumash. In such a case we clearly will not apply the idea of eilu v’eilu.
Even when we do apply “eilu v’eilu divrei Elokim Chaim” it does not mean that halacha l’ma’aseh one has the right to follow whichever opinion he wishes. The original statement in the gemara regarding eilu v’eilu was with respect to the many disputes between Beis Shamai and Beis Hillel and nonetheless the gemara (Berachos 36b) states that, “Beis Shamai b’makom Beis Hille eina Mishna“, i.e. we totally ignore the opinions of Beis Shamai with respect to psak Halacha, and unlike other minority views that were also not accepted, we don’t even consider the views of BeisShamai as creating even the slightest safeik (safeik kol-d’hu.) Regarding Hilchos Aveilus and Orla b’chutz la’aretzm, even when dealing with a d’oraysa issue, the halacha says that in the presence of any slight safeik we go l’hakeil, even if the probability of the doubt is nowhere near 50%. A minority opinion which was not accepted constitutes a slight safeik. But because the views of Beis Shamai were outvoted by Beis Hillel when they met together and debated their issues, their opinions are totally ignored halacha l’ma’aseh. (See my sefer, B’Ikvei Hatzon, siman 38, for more on this topic.)
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Even in an instance where we do apply eilu v’eilu, for example regarding the views of Beis Shamai, one may not follow their opinion. Eilu v’eilu means that one who spends time delving into the understanding of the views of Beis Shamai is fulfilling the mitzvah of Talmud Torah, but it does not mean that it has ramifications halacha l’ma’aseh.
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