I am learning Niddah with ArtScroll. Can someone answer this question from 5a:
5 lines down it says ‘d’pligi rabbonim bein kesumim lriyasa’.
The gemara at this point has just concluded that we paskin l’chumra – that the rabbonim are cholek on R’Dosa by ‘nashim shyeish vestos B’SHAAS VESTON’ (and R’Dosa agrees with them she’lo b’shaas veston’). BUT THIS STATEMENT NOW (‘d’pligi rabbonim…) is saying that at the time of vesston, if they have a riyah- that dayyan sha’aton! That was the first rejected loshon. Why have we implicitly gone back to it?
The first Tosafos on Daf 5 points this out. In the second definition of the Machlokes — that they argue about Shaas Vestan — the Braisa can only be Reb Dosa, since it says that Shelo Beshaas Vesta she is Tamei Me’es La’es. Obviously, Beshaas Vesta we say Dayan Shaatan, which is Reb Dosa.
When the Gemara says that the Braisa is Kulei Alma, it is only in regards to Shelo Beshaas Vesta being Tamei Me’es La’es, says Tosafos.
Haleivi: You missed the point of the OP’s question. d’pligi rabanan is refering to shas veston and therefore can only be r’dosa according to second explanation in the gemara. It is a good question and tosafos does not address it. It seems that at this point the gemara is not getting into the two leshonos, and dpligi rabanan means whoever is the author of the braisa, which would depend on the two leshonos.
Tosafos says that the Braysa can’t be the Tana Kama, according to the second Lashon. This is Rebdoniel’s great answer. I simply wanted to show that it’s true, and from where he got it.