1) CARRYING A WET TOWEL ON SHABBOS
QUESTION: The Mishnah (147a) states that two or more people may carry a wet towel together. One person, though, may not carry a wet towel, due to the concern that he will forget that it is Shabbos and wring out the towel, since there is no one there to remind him that it is Shabbos.
Rebbi Shimon (in the Beraisa) argues and permits even one person to carry a wet towel. To demonstrate that Rebbi also maintains that one person may carry a wet towel, the Gemara records an incident in which Rebbi states that when he was a Talmid of Rebbi Shimon, "We used to carry the towel to a spring where we would wash (and carry the towel back afterwards."
How does this statement prove that Rebbi maintains that one person may carry a towel? Rebbi said, "We used to carry the towel..."! Rebbi's statement seems to demonstrate that one may carry a towel only when he carries it with someone else, contrary to the point that the Gemara attempts to prove.
ANSWER: TOSFOS (DH d'Tanya) explains that when Rebbi said, "'We' used to carry back the towel," he meant that each Talmid took a turn accompanying Rebbi Shimon to the spring, and when the turn of each Talmid came, that individual would carry back the towel by himself. (It certainly would not have been respectful to carry it together with the Rebbi.) "We" means that all of the Talmidim carried back the towel at one point -- each one by himself when his turn came. (It seems from the words of Tosfos that those who argue with Rebbi Shimon maintain that it is not sufficient for one person to carry the towel accompanied by someone else. Instead, both people must hold the towel together.)
How does the Gemara know to interpret Rebbi's statement of "we" to mean "when each one's turn came"?
1. Tosfos explains that it was not proper etiquette for more than one Talmid to go with the master when he went to wash.
2. The RITVA explains that if two or more Talmidim would have carried back the towel together, it would have been a disgrace to Rebbi Shimon (who ruled that one person may carry it by himself).
3. The RITVA adds that since Rebbi made a point of relating this conduct of the Talmidim, he must be teaching something with it. It must be that he meant to say that they carried the towel individually, and he is teaching that he agrees with the ruling of Rebbi Shimon.