There is a debate about whether the result of an interaction between a prohibited and a permitted item should itself be prohibited or not. We generally rule that it should be permitted, but there are many qualifications! What is the logic behind this permissibility, and how is it limited?
Chullin 58
sources:
- חולין נח.
וְלַד טְרֵפָה, רַבִּי אֱלִיעֶזֶר אוֹמֵר: לֹא יִקְרַב לְגַבֵּי מִזְבֵּחַ, וְרַבִּי יְהוֹשֻׁעַ אוֹמֵר: יִקְרַב. בְּמַאי קָא מִיפַּלְגִי? בְּשֶׁנִּטְרְפָה וּלְבַסּוֹף עִיבְּרָה, רַבִּי אֱלִיעֶזֶר סָבַר: זֶה וָזֶה גּוֹרֵם אָסוּר, וְרַבִּי יְהוֹשֻׁעַ סָבַר: זֶה וָזֶה גּוֹרֵם מוּתָּר. אִי הָכִי, אַדְּמִיפַּלְגִי לְגָבוֹהַּ, לִיפַּלְגוּ לְהֶדְיוֹט?
With regard to the offspring of a tereifa, Rabbi Eliezer says that it shall not be sacrificed on the altar, and Rabbi Yehoshua says that it may be sacrificed. With regard to what case do they disagree? It must be with regard to a case where the mother animal was rendered a tereifa and afterward became pregnant from a kosher male, and Rabbi Eliezer holds: In a case where this and that cause it, it is prohibited, and Rabbi Yehoshua holds: In a case where this and that cause it, it is permitted. But if so, rather than disputing whether it is permitted to sacrifice such offspring to the Most High, let them disagree concerning the more basic issue of whether the offspring is permitted to an ordinary person for consumption.
לְהוֹדִיעֲךָ כֹּחוֹ דְּרַבִּי יְהוֹשֻׁעַ, דַּאֲפִילּוּ לְגָבוֹהַּ נָמֵי שָׁרֵי.
The Gemara responds: The dispute addresses the question of whether it is permitted to sacrifice the animal as an offering in order to convey to you the far-reaching nature of the lenient opinion of Rabbi Yehoshua, that such an animal is permitted even as an offering to the Most High.
וְלִיפַּלְגוּ לְהֶדְיוֹט, לְהוֹדִיעֲךָ כֹּחוֹ דְּרַבִּי אֱלִיעֶזֶר, דַּאֲפִילּוּ לְהֶדְיוֹט נָמֵי אָסַור! כֹּחַ דְּהֶיתֵּרָא עֲדִיף לֵיהּ.
The Gemara challenges: But let them disagree concerning whether the animal is permitted to an ordinary person in order to convey to you the far-reaching nature of the stringent opinion of Rabbi Eliezer, that such an animal is prohibited even to an ordinary person. The Gemara responds: It is preferable for the tanna to emphasize the power of leniency.
- עבודה זרה מח:-מט.
מַתְנִי׳ זוֹרְעִין תַּחְתֶּיהָ יְרָקוֹת בִּימוֹת הַגְּשָׁמִים, אֲבָל לֹא בִּימוֹת הַחַמָּה, וְהַחֲזֵירִין לֹא בִּימוֹת הַחַמָּה וְלֹא בִּימוֹת הַגְּשָׁמִים. רַבִּי יוֹסֵי אוֹמֵר: אַף לֹא יְרָקוֹת בִּימוֹת הַגְּשָׁמִים, מִפְּנֵי שֶׁהַנְּבִיָּה נוֹשֶׁרֶת עֲלֵיהֶן וְהֹוָה לָהֶן לְזֶבֶל.
MISHNA: One may plant vegetables underneath an ashera during the rainy season, as the vegetables do not benefit from its shade; on the contrary, the tree’s foliage prevents the vegetables from being properly irrigated by the rain. But one may not plant vegetables under an ashera during the summer, as the shade benefits them. And lettuce may not be planted there at all, neither in the summer nor in the rainy season, because shade is always beneficial to lettuce. Rabbi Yosei says: One may not plant vegetables under an ashera even during the rainy season, because the tree’s foliage [shehaneviyya] falls upon them and serves as fertilizer for them.
גְּמָ׳ לְמֵימְרָא דְּרַבִּי יוֹסֵי סָבַר: זֶה וָזֶה גּוֹרֵם — אָסוּר, וְרַבָּנַן אָמְרִי: זֶה וָזֶה גּוֹרֵם — מוּתָּר?
GEMARA: The mishna records a dispute between Rabbi Yosei and the Rabbis with regard to planting underneath an ashera in the rainy season when vegetables are fertilized by the tree’s forbidden fallen foliage. As the plant is also fertilized by the permitted nutrients of the ground, the plant’s growth is caused by both prohibited and permitted sources. Therefore, the Gemara asks: Is this to say that Rabbi Yosei holds that when both this and that cause it, i.e., when both permitted and forbidden items contribute to a result, the result is forbidden, and he therefore holds that it is prohibited to plant underneath an ashera in the rainy season; and the Rabbis say that when both this and that cause a result, the result is permitted?
הָא אִיפְּכָא שָׁמְעִינַן לְהוּ, דִּתְנַן: רַבִּי יוֹסֵי אוֹמֵר: שׁוֹחֵק וְזוֹרֶה לָרוּחַ אוֹ מֵטִיל לַיָּם. אָמְרוּ לוֹ: אַף הִיא נַעֲשָׂה זֶבֶל, וְנֶאֱמַר: ״לֹא יִדְבַּק בְּיָדְךָ מְאוּמָה מִן הַחֵרֶם״.
Didn’t we hear that they stated the opposite rulings? As we learned in a mishna (43b): Rabbi Yosei says: When one encounters an idol, one should grind the idol and throw the dust to the wind or cast it into the sea. The Rabbis said to him: What is the good of that? That also gives a Jew benefit from the idol, as it becomes fertilizer for their crops, and deriving any kind of benefit is prohibited, as it is written: “And nothing of the proscribed items shall cleave to your hand” (Deuteronomy 13:18).
קַשְׁיָא דְּרַבָּנַן אַדְּרַבָּנַן, קַשְׁיָא דְּרַבִּי יוֹסֵי אַדְּרַבִּי יוֹסֵי!
The contradiction between the statement of the Rabbis in that mishna and the statement of the Rabbis in the mishna here is difficult, and the contradiction between the statement of Rabbi Yosei in that mishna and the statement of Rabbi Yosei here is difficult.
בִּשְׁלָמָא דְּרַבִּי יוֹסֵי אַדְּרַבִּי יוֹסֵי לָא קַשְׁיָא: הָתָם, דְּקָאָזֵיל לְאִיבּוּד — מַתִּיר, הָכָא, דְּלָא קָאָזֵיל לְאִיבּוּד — אָסוּר.
The Gemara explains: Granted, the contradiction between one statement of Rabbi Yosei and the other statement of Rabbi Yosei is not difficult. It may be resolved as follows: There, in the earlier mishna, since the ground-up idol is dispersed and is going to be completely lost, Rabbi Yosei permits deriving benefit from the fertilizer. By contrast, in the mishna here, where the fallen leaves are not going to be lost so quickly, as they fall together on top of the vegetables and provide direct benefit as fertilizer, deriving benefit from them is prohibited.
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וְסָבַר רַבִּי יוֹסֵי זֶה וָזֶה גּוֹרֵם אָסוּר? וְהָתַנְיָא: רַבִּי יוֹסֵי אוֹמֵר: נוֹטְעִין יִחוּר שֶׁל עׇרְלָה, וְאֵין נוֹטְעִין אֱגוֹז שֶׁל עׇרְלָה, מִפְּנֵי שֶׁהוּא פֶּרִי. וְאָמַר רַב יְהוּדָה אָמַר רַב: מוֹדֶה רַבִּי יוֹסֵי שֶׁאִם נָטַע וְהִבְרִיךְ וְהִרְכִּיב — מוּתָּר.
The Gemara asks: And does Rabbi Yosei hold that when both this and that cause it, i.e., when both permitted and forbidden items contribute to a result, the result is forbidden? But isn’t it taught in a mishna (Orla 1:9) that Rabbi Yosei says: One may plant the branch of an orla tree, i.e., a tree during the first three years after its planting, despite the prohibition against eating or deriving benefit from its fruit; but one may not plant an orla nut, because it is a fruit. And Rav Yehuda says that Rav says: Rabbi Yosei concedes that if one planted an orla nut, or sank the shoot of an orla tree into the ground, or grafted an orla tree, deriving benefit from that which grows as a result is permitted. This is apparently because the growth is caused by both a forbidden cause, the orla nut, and a permitted cause, the ground’s nutrients.
וְתַנְיָא נָמֵי הָכִי: מוֹדֶה רַבִּי יוֹסֵי
The Gemara adds: And that which Rav Yehuda says that Rav says is also taught in a baraita: Rabbi Yosei concedes
שֶׁאִם נָטַע וְהִבְרִיךְ וְהִרְכִּיב — מוּתָּר.
That if one planted an orla nut, or sank the shoot of an orla tree into the ground, or grafted an orla tree, that which grows as a result is permitted.
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רַבִּי יוֹסֵי לְדִבְרֵיהֶם דְּרַבָּנַן אֲמַר לְהוּ: לְדִידִי, זֶה וָזֶה גּוֹרֵם מוּתָּר,
And as for the mishna, which seems to indicate that Rabbi Yosei holds that when a result is caused by both permitted and forbidden items it is forbidden, the Gemara explains that Rabbi Yosei was not expressing his own opinion. Rather, when he said that one may not plant vegetables under an ashera even during the rainy season, he said so in accordance with the statement of the Rabbis that a result caused by both permitted and forbidden items is forbidden. Rabbi Yosei said to them: According to my own opinion, when both this and that cause it, i.e., when both permitted and forbidden items contribute to a result, the result is permitted. It is therefore permitted to plant vegetables under an ashera during all seasons.
לְדִידְכוּ דְּאָמְרִיתוּ: זֶה וָזֶה גּוֹרֵם — אָסוּר, אוֹדוֹ לִי מִיהַת אַף יְרָקוֹת בִּימוֹת הַגְּשָׁמִים!
But according to your opinion, as you say that when both this and that cause a result it is prohibited, as seen from your ruling that it is prohibited to plant under an ashera during the summer because of the positive effect of the ashera tree’s shade, you should concede to me, in any event, that planting the vegetables even during the rainy season, when there is no shade, is prohibited, because they are fertilized by the fallen foliage.
- רש”י עבודה זרה מט.
והבריך והרכיב – אם הבריך או הרכיב יחור של ערלה באילן זקן מותרים פירותיהן מיד אע”פ שלא מלאו להן שני ערלה דזה וזה גורם מותר וה”נ אמרינן בעלמא ילדה שסיבכה בזקנה בטלה…
If one sank or grafted the shoot of orlah onto an older tree, their fruit would be immediately permitted even though they haven’t completed the years of orlah, as multiple causation results in a permitted product. And so too we say generally that a newer tree grafted onto an older tree is nullified…
- חידושי רבינו דוד פסחים כו:
ויש לשאול היאך גורם ההתר מבטל גורם האסור ואדרבה היה לנו לומ’ שהגורם של האיסור יאסור את המותר ככל שאר האיסורין שבתורה שאינן בטלין בהתר אלא ברוב והתשובה שלא תמצא זה הדין של זה וזה גורם אלא במאין בהם טעמו ולא ממשו של אסור שטעמו וממשו של איסור ודאי צריכין הן בטול בכל מקום אבל זה לא נשאר כאן לא טעמו ולא ממשו של איסור אלא שנעשה בסיועו כגון זה הפת שנאפה בתנור של איסור שסייע התנור באפייתו וגרם את תקונו אבל לא נשאר בו לא טעמו ולא ממשו וכן כשנאפה בעצי אסור לדעת האומר שאין שבח עצים בפת אין העצים כשאירין בפת לא טעם ולא ממש אלא שנעשה בסיועם ובגמרתם ובגרמתם וודאי שאם נעשה כל האפייה באיסור שלא היה שם סיוע של התר אע”פ שלא נשאר מן האיסור לא טעם ולא ממש הכל מודים שהוא אסור שמ”מ הרי התקון הזה והחדוש שנתחדש בזה הפת הוא באסור ואי איפשר שלא יהיה אסור אבל בשיש שם גורם אחר של התר שאין כל התקון שלו באיסור אלא בסיוע ממנו בזה הוא דעת המתיר האומר שזה וזה גורם מותר מפני שאין כאן לא טעם ולא ממש מן האסור וכל מקום שתמצא זה המחלוקת של זה וזה גורם כך הוא
We could ask: how does the permitted cause nullify the prohibited cause. Au contraire, we could say the prohibited cause should nullify the permitted cause like all other prohibitions in the Torah which can only be nullified by a majority! And the answer is that you will only find the ruling of zeh v’zeh gorem in situations in which there is no actual taste or concreteness of the prohibited substance…
- טור שולחן ערוך יורה דעה קמב
אנן קיימא לן זה וזה גורם מותר בדיעבד אבל לכתחלה אסור לעשות ע”י זה וזה גורם ומ”מ תנור חדש שהסיקו בעצי איסור מותר לכתחלה לאפות בו ע”י היסק שיסיקנו בעצי היתר דחשוב דיעבד כיון שהיה צריך לנתצו אבל תנור ישן שהסיקו מעצי איסור אסור לאפות בו לכתחלה כיון שאין כאן אלא הפסד מועט של דמי העצים ומ”מ אם אפה בו הפת מותרת
We rule that multiple causation renders permissible only post facto but it is prohibited to create on the basis of multiple causation before the fact. Yet in any case a new oven that one fueled with prohibited wood is still permitted for baking even initially if one places permitted wood as fuel, for it is considered a post facto scenario because otherwise one would (lose much money by having to) destroy their new oven. But an old oven that was fueled by forbidden wood, one may not bake in it ab initio because there is only a small loss of the cost of the wood. And yet, even there if one baked in it, the bread is permitted.
- ש”ך יורה דעה ס:ה
בהמה שנתפטמה כו’. כתוב בתורת חטאת כלל ס”ה דין י’ בשם או”ה דלכתחלה אסור לקנות בהמה מן העובד כוכבים שינקה מחלב טמאה ומשמע שם אפילו לא ינקה כל ימיה אסור לקנות לכתחלה ע”ש ובסימנים ולפ”ז כ”ש דאסור לכתחלה להאכילה דברים האסורים וכ”נ ממאי דקי”ל לקמן סי’ קמ”ב סעיף י”א דפרה שפטמה בכרשיני עבודת כוכבים מותרת דוקא דיעבד משום זה וזה גורם אבל לכתחלה אסור אבל במרדכי פרק אלמנה לכ”ג משמע דאפילו לכתחלה מותר להאכילה דברים האסורים ע”ש ונראה דס”ל להמרדכי דאפי’ נתפטמה כל ימיה מותרת דל”ד לפרה שפטמה בכרשיני עבודת כוכבים דאיתא בש”ס פרק כל הצלמים (עבודה זרה דף מ”ט ע”א) דשרי דוקא מטעמא דזה וזה גורם דהתם כרשיני עבודת כוכבים אסורים בהנאה משא”כ באיסורי אכילה שהרי אינו אוכל האיסור עצמו…
An animal that was fed with food used in idol worship (Bavli Avodah Zarah 49a). It is written in the Torat Chatat…that it is prohibited ab initio to buy an animal from a nonJew, as it has suckled nonkosher milk…But in the Mordechai…it seems that even ab initio it is permissible to feed the animal prohibited foods. And it seems that the Mordechai holds that even if the animal ate nonkosher all its life it is permissible because it is not similar to an animal fed food used for idolatry…because in that case the food is also prohibited for deriving benefit, which is not the case regarding something that is merely not kosher – for the person is not eating the nonkosher food themselves.
Some contemporary debates about applying זה וזה גורם –
Note: these sources are merely excerpt from larger discussions and are not meant as a ruling about lab-grown meat or whiskey/scotch aged in sherry casks
- Is Cultured Meat Kosher? https://www.ok.org/consumers/kosher-articles/lab-grown-meat-part-2/
See here for further reading: chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://download.yutorah.org/2024/1053/1099231/the-intersection-between-hilchot-kashrut-and-lab-grown-meat.pdf
In part one of this series, we broadly discussed the technology and process of growing meat in a lab. As a reminder, lab-grown meat is created from stem cells that are fed in a laboratory with specialized culture media. As the cells grow, they are induced to become muscle fibers. The tissue then matures to achieve the desired flavor and texture. We also raised questions about the kosher status of lab-grown meat. This installment will address the first few questions, one at a time.
1. Non-kosher stem cells: If the stem cells originate from a non-kosher animal, does this preclude the resulting meat from being considered kosher?
2. Kosher stem cells: Can the stem cells be harvested from a living kosher animal, or is this a form of eiver min hachai?
3. Salting: Must the animal have undergone melicha (salting to remove the blood), before the stem cells are procured?
The first concern we will address is nonkosher stem cells.
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Even if the starter cells are derived from a forbidden part of the animal, such as muscle tissue, or blood, an argument can still be made that the engineered meat could be kosher. This is based on the ruling of “zeh v’zeh gorem“; whenever there are multiple factors to consider, if one of these factors is forbidden and the other is permitted, the resulting product is often permitted. An example is presented in the Gemara (Avodah Zara 49a). Produce from a field that was fertilized with manure previously used for Avodah Zara, or a cow fattened by consuming beans offered as a sacrifice to an idol, are still permitted. The manure is not the sole cause of the resultant produce, nor is the grain fed to a cow the sole cause of its weight gain. In both cases, there is an additional, entirely permissible, cause. Therefore, the resulting product is permitted.
Lab-grown meat can be produced by a forbidden substance, a non-kosher stem cell. But there is a second element that is necessary for the starter cells to grow and multiply, namely the nutrients introduced into the petri dish that make cell division possible. Therefore, it follows that the cultured meat is the product of zeh v’zeh gorem and might be permissible if the nutrients are derived from kosher sources (even when the original cells are not).
On the other hand, it can be argued that the starter cells are the significantly more critical component, while the nutrients are far less important. Based on this argument, if the starter cells are not kosher, then the resulting meat is also not kosher as this is not an equal or typical zeh v’zeh gorem.
These questions remain heavily disputed amongst poskim today and it is not within the scope of this article to fully adjudicate the arguments on both sides. I am just presenting some of the basic ideas relevant to this question.
- Whiskey/Scotch in sherry casks
https://www.koltorah.org/halachah/whiskey-or-scotch-raised-in-sherry-casks-by-rabbi-chaim-jachter
Whiskey and scotch producers often age their product in barrels previously used to store (non-kosher) sherry wine. There are reasons to be more lenient and more strict in this case.
Although non-kosher wine is not added to the scotch or whiskey, cold liquids stored for more than twenty-four hours absorb into its container. Such absorption is called kavush, which we roughly translate as pickling (another example of cold absorption). Our question is, does aging scotch or whiskey in barrels that absorbed wine taste render it non-kosher?
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Rejected Lenient Approach #1 – Zeh V’Zeh Goreim
It has been proposed to apply the principle of zeh v’zeh goreim to permit liquor aged in sherry casks. This principle refers to when two factors create the result, one approved and the one forbidden, the resulting product is allowed. In our case, the wood and the stam yeinam impact the liquor. Thus, it is similar to the Rama (Y.D. 87:11), permitting cheese created by combining a kosher and non-kosher rennet.
However, this approach is not accepted since the Shach (Y.D. 87:36) clarifies that we permit zeh v’zeh goreim only when the permitted item could have accomplished the result without the forbidden item’s assistance. Since the wood could not achieve the impact alone, the zeh v’zeh goreim principle does not permit the impacted liquor.
