Beraisa: An egg which was laid on Shabbos or Yom Tov may not be handled, and it cannot be used to cover a jar or to support a wobbly bed. A utensil may be moved in order to cover it up. A safek is forbidden and even if it is mixed in with a thousand others, it does not become battel.
Question: If an egg laid on Yom Tov is a D’Rabbanan prohibition, we should be lenient?
Respose: The second part of the Beraisa (about a safek and a mixture) is discussing a new “egg-topic” - eggs of a tereifah, which is D’orayso.
Challenge: If so, why does a mixture not become battel? If it is discussing an egg laid on Yom Tov, it is a davar sheyesh lo matirin, but why shouldn’t a tereifah become battel?
Rav Ashi: The second part of the Beraisa is still discussing a safek D’Rabbonon. But since it’s a davar sheyesh lo matirin [009] and is thus not battel - and - we’re stringent about its safek since it becomes moot as soon as Yom Tov is over.
Beraisa: Acherim quoting Rabbi Eliezer: An egg [laid on Yom Tov] can be eaten, and its mother can be eaten as well.
Question: What type of hen are we discussing? If it is a hen standing to be slaughtered [so the egg can be eaten in accordance with Beis Shammai, 001], of course it can be slaughtered on Yom Tov!
If we’re discussing a hen that is standing for egg production, Rabbi Eliezer surely holds it is muktzeh!
Rabbi Zeira: It means: The egg may be eaten as an adjunct to its mother.
Question: What does this mean?
Abayye: We’re discussing a case where the hen was purchased without a specific purpose. If it is slaughtered on Yom Tov, we know retroactively that that’s what it was bought for and the egg is permitted, but as long as it is not slaughtered, the egg would not be permitted.
Rav Mari: It is discussing a hen standing to be slaughtered, and it was not actually necessary to teach the law of the hen, which is obviously permissible, Rabbi Eliezer is actually just teaching his opinion that the halacha follows Beis Shammai in our Mishna [001], he mentions that the hen is permissible as an expression of exaggeration.
This is as we learned in a Beraisa: Acherim quoting Rabbi Eliezer: An egg [laid on Yom Tov] can be eaten, its mother can be eaten, the chick can be eaten, and the eggshell can be eaten!Explanation: What does it mean that the eggshell can be eaten? The shell is not edible! It must mean “a chick that hasn’t hatched yet and is inside the shell”, but this is surely forbidden, the Chachomim and Rabbi Eliezer ben Yaakov only debate a case where a chick hatched but has not yet opened its eyes, a chick that has not yet hatched is surely forbidden.
So “a chick that hasn’t hatched yet and is inside the shell” must be an exaggeration, similarly, “an egg and its mother” is an exaggeration.