Question: What do Tana d'Vei R. Yishmael and Tana #1 (i.e. of Beraisa #1, 65a) argue about?

Answer: They argue about a species with the four Simanim, but the head is long;

Tana #1 expounds as follows. "That it has legs" is a Klal. "Arbeh Sal'am Chargol Chagav l'Minehu" are Peratim; (Usually, l'Minehu is a Klal. Since it does not resemble the first Klal (see below), Tana #1 does not consider this to be a Klal, Prat and Klal.)

From a Klal u'Frat we learn only the Prat, i.e. only that species. We include (from l'Minehu) only what resembles the Prat in two aspects (Tosfos - both the important and non-important aspects).

Tana d'Vei R. Yishmael expounds as follows. "That it has legs" is a Klal. "Arbeh Sal'am Chargol Chagav" are Peratim. "L'Minehu" is another Klal;

A Klal, Prat u'Chlal teaches what is similar to the Prat, i.e. what resembles the Prat in one aspect (Tosfos - the important aspects).

Question: The latter Klal is unlike the former!

The first Klal ("that it has legs") permits all species with legs. The latter Klal ("l'Minehu") permits only those with all four Simanim!

Answer: Tana d'Vei R. Yishmael expounds Klal Prat u'Chlal even when the Kelalim are dissimilar.

This Beraisa is the source that Tana d'Vei R. Yishmael expounds this way.

(Beraisa) Suggestion: If it is called Chagav, even if it lacks the other Simanim (it is permitted)!

Rejection: "L'Minehu" teaches that this is not so.

Objection: Why would we think to permit it without the Simanim? The Peratim (Arbeh... ) all have the Simanim!

Answer: This objection would be valid had the Torah not written "Sal'am". However, it wrote Sal'am to include species with a long head. One might have thought that it includes even species without the Simanim. "L'Minehu" teaches that this is not so.

Question: The first Tana said that "Sal'am" is Rashon and "Chargol" is Niful. Tana d'Vei R. Yishmael said the opposite!

Answer: Each Tana teaches according to what people call the species in his locale.

(Mishnah): Any fish with Senapir and Kaskeses (fins and scales) is Tahor.

(Beraisa): The following are Tehorim:

A fish that doesn't have scales now, but will grow them later, such as Sultanis (sardine or herring) and Afian (anchovy);

A fish that has scales, but loses them when it leaves the water, such as Akunas, Afunas, Kaspatias, Achspatias, and Atunas.

(Mishnah): Every fish that has scales has fins. Such a fish is Tahor. Some fish have fins but no scales. They are Teme'im.

Question: Since it depends only on scales, why did the Torah say that it must have fins and scales?

Answer: Had the Torah only written "Kaskeses", one might have thought that the word means 'fins' (and he would permit a Tamei fish)!

It wrote both, for clearly one means fins, and the other means scales.

Question: How do we know that Kaskeses means scales?

Answer: "He was clothed in armor of Kaskeses."

Question: Since we may learn from here, why did the Torah need to write both?

Answer (R. Avahu): The Torah added (extra ways to know what is permitted) even though it was not necessary.

(Beraisa): Since the Torah permits fish with Simanim, we know that fish without the Simanim are forbidden. Since the Torah forbids fish without Simanim, we know that fish with Simanim are permitted.

Question: Why did the Torah need to write both?

Answer: This forbids eating Tamei fish with a Lav and an Aseh.

Question: What do we learn from "you may eat all that is in water... "?

Answer: In two places the Torah permitted fish without the Simanim, once explicitly, and once Stam (not explicitly);

Suggestion: The explicit Heter was for fish (without Simanim in water) in Kelim. Perhaps also the Stam Heter permits (only) this!

Rejection: "You may eat all that is in water... " permits bending down and drinking water from a pit or cave (no matter which fish are inside).

Question: Which verse permits fish in Kelim?

Answer #1: "This you will eat, among all that is in water... (in seas and rivers)" - in seas and rivers, we may eat only fish with Simanim, but in Kelim, we may eat fish even without Simanim.

Suggestion: Why don't we rather say that in Kelim, we may not eat even fish with Simanim?

Rejection: "Any fish that does not have fins and scales, in seas and rivers... " - in seas and rivers, we may not eat fish without Simanim, but in Kelim, we may eat them.

Question: We should say that "in water" is a Klal, and "in seas and rivers" is a Prat. A Klal u'Frat includes only the Prat, i.e. seas and rivers, but not Charitzin u'Ne'itzin (channels of flowing water. There, all fish are permitted)!

Answer: The Torah gives another Klal "in water" (so we expound a Klal u'Frat u'Chlal).

Question: The two Kelalim come together, and the Peratim are after them! (This is not a Klal u'Frat u'Chlal!)