On 9b, the Gemara introduces Rabbi Natan's opinion by saying that "our Mishna is not like that tanna (i.e., Rabbi Natan)". However, Rabbi Natan actually seems to be explaining our Mishna in a different way, not arguing on it. Is this a common way of introducing another explanation of a Mishna? The wording seems strange.
Paul Kandel, Haifa
Dear Paul,
Hello there and thanks for your question. The explanation is as follows. There is a dispute between Beis Shammai and Beis Hillel respectively. Rebbi who compiled the Mishnah states the Machlokes in a certain manner as appears in our Mishnah. Rabi Nasan who is a Tana explains the Machlokes in a different manner and is quoted in a Beraisa. Rebbi Nasan is not an Amora expounding on the Mishnah, but rather a Tana with a different opinion than that quoted in the Mishnah. (In other words the Machlokes between Rebbi Nasan and another (nameless) Tana, existed before the Mishnah was compiled by Rebbi. Rebbi preferred the opinion of the other Tana over that of Rebbi Nasan's.)
All the best.
Y. Landy