1) THE IDENTITY OF "BNEI YAMA"
OPINIONS: The Beraisa relates that "Dolfinin" reproduce like people (or from people, according to the Girsa of the SHITAH MEKUBETZES and RASHI).
The Gemara asks, what are these "Dolfinin," and Rav Yehudah answers that they are "Bnei Yama." What exactly are these Bnei Yama?
(a) According to the Girsa of the Gemara as it appears in our text, "Dolfinin" may refer simply to a type of cetacean mammal, such as the whale or dolphin. This is especially likely considering the similarity in the words themselves. Dolphins indeed reproduce "like people," bearing live offspring (instead of laying eggs like fish). They also are one of the most intelligent creatures in the animal kingdom, and thus the appellation of "men of the sea" is fitting.
The TOSEFTA (1:5) describes Dolfinin further and says that they "bear and raise young as man does." This can be understood to mean that they cohabit "face to face," as dolphins indeed do, and that they nurse their young with milk and stay with them even after they start to mature, unlike other fish and animals.
The MUSAF HA'ARUCH (Erech "Dolfin") records that the Greeks and Romans referred to a certain large fish (perhaps the dolphin) with these characteristics as "the man of the sea."
(b) However, according to the Girsa of RASHI and TOSFOS (DH ha'Dolfinin, based on a version of the Tosefta that does not appear in our text), the Bnei Yama reproduce "from" humans. Since interbreeding between dolphins and humans is not possible, these Dolfinin must refer to a much more humanlike creature, as Rashi (DH Bnei Yama) explains: "there are fish in the sea whose form is half-human and half-fish." Rashi translates the "Bnei Yama" as "sereine" in Old French. Rashi clearly is referring to the siren, or mermaid, a mythical creature with the tail of a fish in place of legs.
The TORAS KOHANIM (Parshas Shemini 3:7) also discusses a creature called the "Sironis," which the ARUCH (Erech "Sironis") and RA'AVAD describe as a siren or mermaid. The Toras Kohanim says that one might have thought that the corpse of a "Sironis" is Metamei b'Ohel (like the corpse of a dead person), and thus the Torah specifically excludes it (Rebbi Chanina argues and maintains that it is Metamei b'Ohel). Translating the "Sironis" as a siren or mermaid is supported by the fact that the Toras Kohanim finds it necessary to enlist a verse to teach that this creature is not Metamei b'Ohel like a person.
The RA'AVAD explains the logic for why a Sironis could be Metamei b'Ohel. The Torah tells teaches that Tum'as Ohel applies to "Kol Nefesh Adam" (any soul of a person), which might include anything that people call "man" -- such as the siren, which is called "the man of the deep." In that case, whether or not mermaids actually exist, it is necessary for the Torah to teach that they are not Metamei b'Ohel. We must know how to deal with other sea-creatures to which people commonly refer as "man of the sea" (such as dolphins) or a similar name, due to their similarity in some respect to man. (M. KORNFELD)
(For additional sources that discuss the identity of the "Dolfinin," contact Kollel Iyun Hadaf.)
2) FISH BEFORE THE TIME OF YONAH
QUESTION: The Gemara says that only man, fish, and snakes cohabit "face to face," unlike all other creatures. The Gemara explains that the reason why fish reproduce in this manner is that Hash-m spoke to fish (as related in Yonah 2:11, when Hash-m told the fish to return Yonah to dry land).
Does this mean that fish changed their nature at that point in history, such that before Hash-m spoke to the fish, they reproduced like other animals, and after Hash-m spoke to the fish, they reproduced like man, "face to face"?
ANSWER: RAV YAKOV EMDEN explains that Hash-m originally created fish to behave in this manner, because in the future He would speak to them.

8b----------------------------------------8b

3) AGADAH: "SHOW US A LIE"
QUESTION: The Gemara records a series of exchanges between Rebbi Yehoshua and the Elders of Athens. When read literally, their dialogues seem to have little or no meaning. It is not conceivable, however, that the great Rebbi Yehoshua and the wisest men of the Roman Empire would involve themselves in debating trivial matters. It must be that the dialogues between Rebbi Yehoshua and the Elders of Athens involved deeply profound matters that touch upon the most fundamental aspects of existence. Their words were veiled in allegories, and the lessons that they taught involve profound truths about Jewish destiny. (See also Insights to Bava Basra 73:1.)
In one of the interactions recorded by the Gemara, the Elders of Athens said to Rebbi Yehoshua, "Show us a lie."
Rebbi Yehoshua replied, "There was a mule that gave birth. A note was hanging from it, on which was written, 'My father's estate owes one hundred thousand Zuz.'"
They said to him, "But can a mule give birth?"
Rebbi Yehoshua said, "That is why it is a lie."
What is the meaning behind this cryptic exchange?
ANSWER:
A number of explanations for this Gemara are given by the commentators. The VILNA GA'ON, in "Perush Al Kamah Agados" (Vilna, 1840, reprinted with notations and sources by Rav Aharon Feldman, Feldheim Publishers; see also Rav Feldman's English elucidation of the Vilna Ga'on's commentary in "The Juggler and the King," Feldheim Publishers), explains that the subject of the debate was the continued existence of the Jewish people after the destruction of the Beis ha'Mikdash, and their eventual return to Yerushalayim. The following is a summary of the Vilna Ga'on's comments about the mule born with the promissory note.
Regarding "the falsity" that the Elders of Athens asked Rebbi Yehoshua to show them, the Vilna Ga'on explains that the Gemara in Avodah Zarah (11b) records that the Romans used to taunt the Jews by proclaiming, "The master's reckoning is false, the brother of our master, a fraud." They were slandering Yakov Avinu (and his descendants, the Jewish people), proclaiming that the blessings he received from Yitzchak were false and that Esav (and his descendants, the people of Rome) is heir to the prominence of Yitzchak. The Gemara there quotes Rav Ashi who responded that their own words refute them. Had they said, "The fraud -- the brother of our master," then their words would have been understood as they intended. However, the wording that they used -- "the brother of our master, a fraud" -- implies that their own master is the fraud!
The Romans were proclaiming that the Jewish people have no hope of being redeemed, and no future to anticipate. The blessings they received from Yitzchak will not materialize. They will forever be subject to Roman oppression, if they survive at all. Rav Ashi responded that it is the nation of Rome that is the fraud. The Romans, and not Yitzchak or Yakov, were speaking falsehood when they said that they, and not the Jewish people, were the blessed nation. Similarly, when the Elders of Athens asked Rebbi Yehoshua to show them a lie, they were asking him to show them why the declaration of their kinsmen, that "the master's reckoning is false," is itself a lie.
Rebbi Yehoshua responded with a metaphor about a mule. The Jewish people are called an "Akarah" (Yeshayah 54:1), a barren woman, who -- like a mule -- seems to be unable to bear children. During their many years of exile, the Jews are constantly trampled and denigrated. They seem to have no hope for the future, like the barren woman who despairs of bearing children. The Jewish people are bereft of their children, their future.
However, there is a note of debt hanging from the mule. This debt refers to Hash-m's promise to Avraham Avinu that his offspring eventually will be redeemed from the exile. When the time of the final redemption comes, it will become evident to the entire world that the Jewish people are not a barren mule, but they are a fertile nation with an illustrious future. The "mule" will indeed give birth.
How, though, did Rebbi Yehoshua's metaphor prove to the Elders that the final redemption is certain to come? The prophet Yeshayah states, "Sing, you barren woman who has not given birth, for the children of the desolate woman will be more than the children of the married woman" (Yeshayah 54:1). If she will have children, why is she called barren, and if she is barren, why should she sing? The Gemara in Berachos (10a) explains that the verse means, "Sing, Jewish nation, even when you are like a barren woman, for you have not borne children who are destined for Gehinom [like the nations of the world]." The barren woman only appears to be barren, because her children have been exiled. She still rejoices, though, because she knows that through their suffering in exile they will learn to return their hearts to their Creator and thus will earn eternal reward and avoid Gehinom. The very exile that caused the Romans to believe that the Jewish nation will never be redeemed is itself the key to redemption. If the Jewish nation appears hopelessly barren like a mule, it is because they have been guaranteed redemption. When the Elders commented that the Jewish nation is barren ("But can a mule give birth?"), Rebbi Yehoshua responded, "That is why it is a lie" -- that is, "It is that very fact -- our appearance, in exile, as barren -- that will eventually prove your statement (that we will not be redeemed) to be a lie!"

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