By Rabbi Shmuel Wise

Welcome to Perek Eilu Treifos! Although much of the unique challenge of this chapter is the task of deciphering the numerous anatomical facts that are referred to, we also get to engage with plenty of classic Shas principles through the pages of Eilu Treifos. One important Shas principle that resurfaces in Eilu Treifos is the concept of chazakah: That when an uncertainty arises, we presume the object of our uncertainty retains its previously known status.

On Wednesday’s daf (43b), the Gemara discusses a situation where there is cause for concern that an animal became a treifah. For instance, a dangerous predator was known to have been in close quarters with a flock — presenting the possibility that any one of the animals may have been attacked and rendered a treifah. The Gemara tells us that the halachah in this case is disputed by the Amoraim: one opinion says the animal is presumed kosher, the other says it is presumed treifah.

Tosfos asks on the stringent opinion: Why doesn’t he apply the principle of chazakah and say that if we’re not sure whether the animal became a treifah, we should be allowed to assume that its previous status didn’t change? Tosfos answers that according to this view we cannot rely on chazakah here because of the strong likelihood that the animal was indeed attacked. But wait: How could Tosfos even suggest going by chazakah here considering the fact that the event that led to the uncertainty (i.e. the lurking predator) occurred at a time when the animal was certainly prohibited (since it was still alive)? This prohibited status should establish that, just the opposite, the animal must be presumed non-kosher!

Tosfos himself addresses this point and proves from a Gemara in Yevamos that a forbidden status does not influence the question before us when the particular forbidden status cannot be applied to the current situation. Consider: The reason why the animal was forbidden at the time of the lurking predator was because of the prohibition against eating a live animal. That prohibition obviously does not pertain to the animal before us which is quite dead (for we have done shechitah to the animal).

The Rashba and the Ran argue with Tosfos in this matter. In their view, if the event that gives rise to the halachic uncertainty happens while the animal is prohibited, that prohibited status indeed establishes a new chazakah, and we thus presume the animal to be prohibited until it can be established otherwise. The Rashba brings a proof against Tosfos from the Gemara we learned in early December (9a) which deals with a case where we are not certain whether an animal received a proper shechitah. The Gemara rules that we follow chazakah: Since while the animal was alive it was prohibited, we must continue to assume that it’s prohibited in the face of the questionable shechitah. We see then that the halachah does continue to recognize a chazakah—even when its underlying reason is no longer relevant!

What could Tosfos respond? Perhaps Tosfos would say the following: What is the basic concept of shechitah? Through the law of shechitah, the Torah essentially says that through a specific method of killing, we “make” the animal into something permitted for consumption. Viewed through such a lens, the Rashba’s question doesn’t begin: The previous status in the case of 9a was an animal which was not yet made into a kosher animal. The fact that we might have made it into a kosher animal is not a sufficient basis to establish that that actually occurred — a classic application of chazakah.

Rabbi Wise is maggid shiur of Real Clear Daf, a website and mobile app that offers free audio shiurim and other resources to assist your journey through Shas. He is also the director of Tehillim Together, a mobile app (for iOS and Android) that offers a translated sefer Tehillim and facilitates Tehillim groups. To be a sponsor or to reach Rabbi Wise, please write to or call 855-ASK-RCD-1 (275-7231).


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