The Mystery of Rav's Halacha

After reviewing the two possibilities which the Gemara has presented to date - as to what Rav Yehuda/Rav meant when he said עד זומם משלם לפי חלקו - we continued to the new approach of Rava  באומר עדות שקר העדתי - Rav was speaking of a case in which the witness said/admitted that he had testified falsely.

Explaining Rava hinges on two factors:
a) understanding Rava's scenario
b) once that is clear, answering the question as to how this new scenario generates an obligation for the witness to pay

We went "back and forth" with numerous creative suggestions; some suggested that he had gone to a different Bet Din and admitted this; we noted that admission of his lie should exempt, not obligate him, at least - according to Rabbi Akiva....One student responded that maybe Rava paskens like Rabanan of the earlier Baraita, for whom admission of hazama does not generate an exemption, but an obligation........

Then we saw the ב"ח - commentary of the "Bayit Chadash" - R. Yoel Sirkes  - on the Gemara.  He explains that the obligation to pay is based on a principle called דינא דגרמי and that the term עד זומם is לאו דוקא ie not literally an עד זומם but rather an עד שקר - a false witness.

We explained: 
The scenario, according to the Bach, is not a case of עדים זוממים at all! Rather, it's a case where edim, for eg, testified that Reuven owes $1000 and he actually ends up paying the thousand dollars.  Later, one of the edim admits that he lied.  Rava/Rav Yehuda-Rav are holding that this witness is חייב based on a principle of דינא דגרמי, the details of which can be found in the most recent post.  It is a halacha in the dinim of indirect causation that triggers the payment, not a special "chiddush" of כאשר זמם ....He is paying independently, as a מזיק - one who caused damage...

Now this seemingly requires a bit of a logical jump - since Rav used the term עד זומם -while this explanation takes him less than literally...But, we explained, this may be the point of the Gemara: that the original statement of Rav, which the Gemara had cited ASSUMING that the din quoted relates to "classic ed zomem" rules - is really totally unrelated to the din of edim zomimin.  After two suggestions that failed:
a) because one principle was already in a mishna
b) because the second explanation contradicts the known rule (baraita) that no classic ed zomem will pay unless both are "huzam"

...the Gemara is forced to explain Rav as making a statement unrelated to edim zomimin. And we explained that this pshat is okay.  Why? Rav was not speaking in the context of our sugyah: our Gemara cited this statement of Rav, assuming that he was. Analysis proved otherwise...

We ended the discussion with the first words of Tosafot, who says, after quoting Rav, ושוב הוזם - meaning - after the witness said עדות שקר העדתי - he was הוזם ! This comment shows that Tosafot does NOT go in Bach's direction at all - but tries to make sense of Rava by sticking to the format of classic עדים זוממים...Tonight's shiur will be dedicated to figuring out how Tosafot learns our sugyah!