Answer: (Ri): Rabanan who argue with Rebbi do not expound this way. Rather, in Sanhedrin (64b) R. Yishmael and R. Akiva expound it differently.

Implied question: We should count it, according to Rebbi!

Answer: We cannot, for there we say that the number (36) teaches that if one transgressed all of them in one Helam (forgetting), he is liable for every one;

According to Rebbi, one is liable a Chatas only for something for which b'Mezid one is liable a Lav and Kares;

Citation (Yevamos 9a - Rebbi): It says here (regarding Korban Chatas) Aleha, i.e. "v'Nod'ah ha'Chatas Asher Chat'u Aleha", and it says below [regarding marrying Achos Ishto] "Aleha b'Chayeha";

Citation (cont.): Just like there, one is Chayav Kares for the Aveirah, also here. i.e. "v'Nod'ah ha'Chatas Asher Chat'u Aleha";

Citation (cont.): This excludes these (Porek Ol, Megaleh Panim b'Torah, and annulling Bris of the flesh). Even though they are included for Kares, there is no Lav forbidding them.

Explanation: We could not answer like this for Rabanan. They do not require a Lav, for they hold that "Torah Achas Yihyeh Lachem" equates the entire Torah to idolatry;

Just like one who is Mezid is Chayav Kares for idolatry, [one brings a Chatas for such Aveiros b'Shogeg]. They do not require a Lav.

Implied question: [They should require a Lav, for] a Lav forbids idolatry!

Answer: There is also stoning for idolatry, and even so Rabanan obligate Chatas even where there is no Skilah!

The Hekesh [of the entire Torah to idolatry] is only regarding Kares, which is written there - "Hikares Tikares";

Similarly, we do not require a Lav for a Chatas.

Support: In Makos (13b), we exclude Pesach and Milah [from Chatas], for Chatas is only for [transgression of] Mitzvos like idolatry, which are fulfilled through inaction. This excludes Pesach and Milah, which are fulfilled through action.

If we required a Lav for Chatas, the Gemara should say that idolatry has a Lav, so we exclude these (Pesach and Milah).

Even if they were fulfilled passively, one would not be liable for them, since they have no Lav.