Thursday, October 14, 2010

Science and Halachah

Today's battles of Science and Torah are often taken as occurring in a vacuum - as though someone woke up yesterday and realized that there may be some issues regarding the age of the universe, or some other cause celebre.

One result of this perspective is that authorities who take positions on either side of the issue - (1) Hold the line against the influence of modern research, or (2) Amend our understanding of the way the world works - are often accused of holding insidious or subversive agendas, trying to maintain their political power, etc.

In reality, though, the lines on this were staked out at least 700 years ago, in early debates about halachic rulings which seemed to depend on incorrect science. Of course, the question of accepting secular research goes back long before that, and is negotiated in the gemara itself, but the specific question of: "The sages believed X and based their halachic rulings on X, and now the world thinks/believes/proves that X is wrong - what do we do?" is first clearly hashed out in the responsa of the 12th to 14th centuries.

I intend to use the next session or two of my "Responsa that changed Jewish History" series to look at the positions outlined in those responsa, and the support brought for those positions. For a taste, here's a classic example of the responsa of that era: Rashba, Volume 1, Responsum 98. The translation, which is only partial, is my own.

Question: An animal was found to have an extra eiver [yeteret], from one of those eivarim which renders the animal a tereifah, in a place which should render it a tereifah. It was clarified that twelve months had passed. Would we say that since twelve months passed it is not a tereifah, and it is kosher, for Chullin 58 says that a tereifah cannot live twelve months? Although I have seen and heard that some permit this and are lenient, I wish to know your view.

Response: If you saw or heard one who is lenient and permits a yeteret, or any other situation the sages listed as a tereifah, do not listen to him, do not agree with him, there should not be such in Israel. It appears to me that one who permits this is slandering the words of the sages. I will speak with you about this at length, so that a fence will be built for you and for all who tremble at the word of Gd, and the words of the holy sages of Israel will not be made like a fence that has been pushed aside, such that a fox could ascend and break through.

In Chullin 42, the sages listed, “There are eighteen tereifot… This is the rule: If an animal that suffers such a wound cannot live, it is a tereifah.” And the gemara comments that the author of the mishnah believed that a tereifah cannot live, and that which he had learned he listed, and that which he had not learned he did not list. The list is brought with “Zeh haKlal,” and we depend on “Zeh haKlal” formulations in the gemara. Some sages added other tereifot, situations in which the animal could not live, according to their views, and they depended upon this rule… There is a view there in the gemara that when the mishnah says it “cannot live,” this does not refer to living twelve months alone, but rather that it will eventually die from that wound… In any case, all those listed there, and included by the sages, cannot ever be permitted.

Ulla included all of the tereifot in eight categories, saying (Chullin 43), “These eight categories were told to Moshe at Sinai: Pierced, split, removed, lacking, torn, trampled, fallen and broken.” We say that these were told to Moshe at Sinai, and yeteret is among those that were removed, according to Rav Huna, or those that are pierced or split… And Rav Huna’s position is definitive, and none have ever argued it… For all of these, they never said that living twelve months or giving birth would be a sign [of health], for there is no sign in the survival of known tereifot, and they are prohibited unconditionally. We don’t say that we leave them [to see if they survive], for according to the view that a tereifah cannot live, they cannot live. One who said that they survived two or three years was describing something that never happened, and who testifies to this is mistaken; such never happened.

It is as we say in the gemara: “R’ Yosi ben Nehorai asked R’ Yehoshua ben Levi: How big a hole in the windpipe?” And he replied, “It is as we learned…” R’ Yosi ben Nehorai replied: But we had a lamb like that in our area, and it lived! To which R’ Yehoshua ben Levi replied, “You depend on this? The law has spread in Israel that a bird with a fallen thigh is a tereifah, and R’ Shimon ben Chalafta had such a chicken and he prepared a tube for it, and it lived, and that was only within twelve months, and the same must be true for your case.” Therefore, even if many people go about saying they saw this, we contradict them. The words of the sages will stand, and we will not slander the words of the sages and uphold the words of these others.

In cases like these I say: Please do not slander the words of the sages regarding that which they considered a definite tereifah, and they did not leave as a doubt.

And if there is one whose heart disturbs him, saying that perhaps the sages only spoke of the majority of cases and most animals experiencing one of the listed tereifot will not survive, but some of them might survive due to their physical and constitutional strength, then you will have cancelled our mishnah’s rule of “None like this live.” All of those listed by those sages, within the view of the mishnah’s author, cannot live… And if this were true that we had seen it live, this would be testimony that the animal is not among the tereifot. Further, it would be testimony not only about itself, but it would be ‘purifying’ itself and its peers. You cannot escape one of two possibilities: Either a tereifah cannot live and the fact that this animal lived testifies that it is not a tereifah, or this case resolves the debates [regarding whether a tereifah can live] and testifies that the law is against the author of the mishnah, and like the author of the baraita who stated that a tereifah can live…

And if you will reply: What can we do – we have seen a yeteret of the foot survive twelve months, with our own eyes! This is what R’ Yehoshua ben Levi told R’ Yosi ben Nehorai, “You depend on this?” Meaning: This is not possible. It is as though you testify that you have seen the impossible. Or, there is another cause. So, too, here we ask the witness how he knows that this animal had, in fact, survived that period. Perhaps you forgot or erred, or perhaps you were confused regarding the time, or perhaps you confused this animal for another, for it is not possible to testify that this animal was in his sights for the entire twelve months. And if he will strengthen himself in his error and say, “No, for I love these strange words, this is what I saw and this is what I will follow,” then we will tell him that it is impossible to slander the words of the sages. The witness, and one thousand like him, should be cancelled, rather than cancel one point of the positions agreed upon by the holy Jewish sages, the prophets and students of prophets, and statements given to Moshe at Sinai…

Much more in the class itself, of course...


  1. There are many times in the Talmud where there is what sounds to be an absolute rule which is later circumscribed to specific circumstances (e.g all the mishnayot that state ein bein x to y ela a,b and c - where the gemara in order to achieve coherence later says the list is incomplete)
    Joel Rich

  2. Joel-
    True, but Rashba and others specifically address and deny that possibility in this case.

  3. I know- and I always wonder whether they had a mesorah to that effect.
    Joel Rich

  4. Rashba specifically traces it to the gemara's own debates.

  5. What about R. Hai's famous statement that we don't accept the medicine of Hazal because "they are hakhameinu, not rofe'enu"? How does that apply to other more halakhically oriented topics? Moreover, if they can be wrong with medicine, why could they not be wrong with more abstract scientific subjects?

  6. In this case there is also another approach that reconciles the Gemara's statement with observation: that the rule ("a tereifah cannot live twelve months") indeed applies only to acquired deficiencies, not to congenital ones like extra limbs.

  7. So why did the chatam sofer have to (what I'm told did not appear before his time) posit that the rules were set at the end of the year 4000 and no changes in nature after that get reflected.

    Joel Rich

  8. Joseph-
    I do include that in the shiur, but only to show it's non-relevance to the issue of halachah. The Gaonic claim (which I believe is also attributed to Rav Sherira Gaon) is specific to medicine, as noted in the text itself.

    Anonymous 10:44 AM-
    On what basis would we make such a distinction?


  9. From an old Avodah post:>> The Chazon Ish writes in Yevamos 57:3... even though the nature of
    >>animals has changed (nishtanah hateva) in regard to treifos, since
    >>the halachos were determined during the 2000 years of Torah (from
    >>Avraham to appr. the close of the Mishnah) they cannot be changed
    >>based on current nature.

    >> However, in other places that he mentions nishtanah hateva he
    >>recommends changing halachah. For example, in Yoreh Deah 155:4 the
    >>Chazon Ish permits violating Shabbos for the needs of a baby born
    >>in its eighth month because nishtanah hateva and the baby is
    >>viable. Why doesn't he say that the halachah must remain as it was
    >>established during the period of Torah?

    Joel Rich

  10. Joel-
    Yes, that's what I thought you might have meant - Chazon Ish, not Chasam Sofer.

    In any case: Chazon Ish's approach seems to be a new way to deal with Rashba's fundamental problem. Evidently, denying the evidence of our eyes became untenable, and so another approach was needed.

  11. I haven't seen the quote in a while, so it may have been R. Sherira. But in any case, based on what logic would be distinguish between medicine and other natural phenomena? Are they not both reflecting the same physical reality?

  12. Joseph-
    I expect to include it in my Daily Torah Thought on Sunday, so you can see it then. In any case: He only says that when the sages recorded medicines, they were recording the medicine of their day. He makes no broader comments about their scientific knowledge, or halachah.

  13. oops-sorry about the multitasking :-)
    Shabbat Shalom

  14. Thanks, I saw the daily thought, but I still don't see a logical reason to distinguish between medicine and other physical phenomena, the knowledge of which also comes from contemporary science.

  15. Joseph-
    As I see it, this is different because he specifies that the medical presecriptions are not intended as halachic statements. The implication is that they are more precise with halachic statements.

  16. Oh, come on, Joseph - Why did you accept that answer?

  17. Do you have a better one? :)

    I accept it only as a way of understanding your distinction; I'm not necessarily convinced of the actual truth of the statement. To clarify, I understand if you would posit that because rabbis are more precise with halachic statements, they are more likely to test alternative theories before issuing a ruling on terefah.
    However, even then, as I said before, any type of scientific judgment is subject to the most recent theory, so I am still not convinced they are infallible on that issue based on your answer- particularly if, in fact, the rabbis can err when ruling (ואם כל עדת ישראל ישגו). Otherwise, why Maseches Horayos?
    If I really wanted to continue to debate, I can ask about alternative shitos aside from the Rosh, but my evidence comes more from hazy memory - i.e. I remember a rosh yeshiva who is expert in biology giving a speech in which he seems to connect this geonic statement to the fallibility of the Talmud (hatzi achbar-hatzi adamah?), as well as the Rambam's trying to combine science with troublesome halakhos as much as possible (isn't he the one who holds that salt removes only the blood on top of the meat?). Again, I'm not "holding" in the sugya, so I can't cite confidently. I likewise recall discussing the issue of bugs in fruit(spontaneous generation vs.microbiology)and beli'ah.
    If we assume that Hazal cannot err regarding these things, then there's no more discussion, though we could question how the Rosh could hold of this infallibility based on existence of pesukim and mishnayyos implying they can make mistakes. If we assume they can err, then we'd have to square the observance of certain halachos as minhag avoseinu and a let a future Sanhedrin change the halacha based on their understanding of the reality.

  18. Joseph-
    [Think you mean Rashba rather than Rosh]
    I meant something simple: If chazal took medicine seriously - and they did, as evidenced by חמירא סכנתא מאיסורא and their decision to include therapies in the gemara - then why were they not as careful in investigating facts relating to saving lives, as they were in investigating facts that relate directly to halachah?

  19. The way I understood what you were saying is that the geonim, who were the most direct heirs to the mesorah of Bavli, understood that not everything in the Gemara represented the normative opinion, and that the gemara would often delve into a discussion not intending for everyone to take the conclusion as authoritative. Therefore, when some of these "cures" were included, they were not meant to be presented as absolute. The point is that Chazal were not doctors and therefore never intended for their positions on medicine to substitute for real science. Of course, if this is the case, then the obvious question would be why bother recording any of these cures at all, and wouldn't such recording be misleading? (And yes, I meant Rashba, my fault for rushing a response.) Your question is more sophisticated than this because it holds Chazal responsible for checking their facts in a situation in which lives are at stake. What do you think? Does the geonic position hold up to scrutiny, or do we need to accept Tosafos' nishtannah ha-teva? Or perhaps we can distinguish between what was stated in a back-and-forth discussion in a beis medrash and a more authoritative text such as a mishnah/baraisa?