Rabbi Yochanan pointed out a contradiction in the opinion of Rabbi Yehuda:
Mishna: One may not squeeze fruits for juice on Shabbos or Yom Tov, if juice flowed from grapes and olives without being squeezed, the juices are forbidden.
Rabbi Yehuda: If they were prepared for food, their juice is permitted, if they were prepared for juicing, the juice is forbidden.
Rabbi Yochanan: So we see that according to Rabbi Yehuda, anything that comes from something prepared for food is consider like “a small piece of bread that was removed from a loaf”.
Mishna: Rabbi Yehuda: One can eat tevel by making a condition. Similarly, an egg laid on the first day of Yom Tov may be eaten on the second day.
Rabbi Yochanan: It is only permitted on the second day but it is forbidden on the first day! Shouldn’t it be considered like “a small piece of bread that was removed from a loaf” - just like juice?
Rabbi Yochanan: We must invert the opinions in the first Mishna: The Chachomim differentiate between fruits prepared for food or for juicing, while Rabbi Yehuda always forbids it.
Ravina: We need not invert the opinions. In the second Mishna, Rabbi Yehuda is only talking according to the position of the Chachomim. “My opinion is that it is like a sliced bread and is permitted, but you should at least admit that on the second day it is permissible”.
The Chachomim, however, disagree: “Rosh Hashana is different because both days are one kedusha.”
Ravina brei D’Rav Ulla: The second Mishna is not discussing a hen raised to be slaughtered. An egg from such a hen would indeed be comparable to a sliced piece of bread. The Mishna is discussing a hen standing for egg production, thus Rabbi Yehuda, according to his strict position with regard to muktzeh, forbids such eggs. [The reason Rabbi Yochanan asked the question in the first place is because the Beraisa didn’t specify what type of hen the egg is from, and it seems to include also hens intended for slaughter].
Mishna: An egg which is laid on Yom Tov: Beis Shammai: It may be eaten. Beis Hillel: It may not be eaten.
Rav Nachman: The egg is muktzeh.
Rabbah: The egg is forbidden because of Hachana.
Rav Yosef: The egg is forbidden because of gezeiras peiros hanoshrin.
Rav Yitzchok: The egg is forbidden because of gezeiras mashkin shezavu.
Challenge: Beraisa: An egg which was laid on Shabbos or Yom Tov may not be handled [it is muktzeh], and it cannot be used to cover a jar or to support a wobbly bed [this can be accomplished if you know how to handle an egg properly]. A utensil may be moved in order to cover it up [although it is completely muktzeh, like a stone or money, it is still permitted to handle something permitted in order to protect it]. A safek is forbidden and even if it is mixed in with a thousand others, it does not become battel.
This [that a safek is forbidden] would be right according to Rabbah, because it is a safek in a Torah prohibition, but according to Rav Yosef and Rav Yitzchok, it is a safek in a D’Rabbanan position and we should be lenient?
[This question is not asked about Rav Nachman’s opinion because muktzeh is stricter than a standard D’Rabbanan, Tosfos.]