YUTorah on parashat Acharei Mos and Kedoshim

Audio Shiurim on Acharei Mot-Kedoshim Rabbi Kenneth Brander: The Jewish Notion of a Sexual Ethic  Rabbi Chaim Brovender: Molech Rabbi Ally Ehrman: The Weak Child  Rabbi Chaim Eisenstein: Kedushat beit hamikdash, consistency, permanence  Rabbi Daniel Z. Feldman: Lifnei Iver Lo Titen Michshol Rabbi Joel Finkelstein: Beauty and Judaism  Rabbi Efrem Goldberg: Sanctity of Marriage Under Attack  Rabbi Yehuda Goldschmidt: Serve Hashem with Direction Rabbi Yonah Gross: Understanding Chukim  Rabbi Shalom Hammer: The Affect of Self Security  Rabbi David Hirsch: The Connection Between Acharei Mos and Kedoshim Rabbi Aharon Kahn: Being a Separate Nation Rabbi Yisroel Kaminetsky: Hevey Mitalmidav Shel Aharon Rabbi Eliakim Koenigsberg: The Lesson of Rabbi Akiva Rabbi Akiva Koenigsberg: The concept of Aseh doche Lo Taaseh Rabbi Aryeh Lebowitz: Normalizing Spirituality  Rabbi Shmuel Marcus: Sefer Hachinuch on Kedoshim  Rabbi Dovid Miller: Bringing Avoda into Everyday Life  Rabbi Yaakov Neuburger: Importance of Maintaining Kedusha in Eretz Yisroel Rabbi Zvi Romm: Coming Back To Eretz Yisrael Rabbi Hershel Reichman: Everything is in Hashem's Will  Mrs Ilana Saks: Defining Elements: When Not to Go for the Gold  Rabbi Avi Schneider: Kedoshim- An Opportunity or an Obligation  Rabbi Baruch Simon: Steadfast Kedusha: One Step at a Time  Mrs. Shira Smiles: Life Force  Rabbi Zvi Sobolofsky: To separate the holy and the mundane  Rabbi Aaron Soloveichik: Aspiring to Kedusha  Rabbi Reuven Spolter: To Life!  Rabbi Moshe Taragin: Improving Perfection  Rabbi Michael Taubes: Fourth Year Produce  Rabbi Moshe Tzvi Weinberg: The Dangers of Passive Judaism Rabbi Andi Yudin: Dan Lekaf Zechus  Rabbi Ari Zahtz: Ve Ahavta LeRayacha Kamocha  Itamar Zolberg: Kedushah v'Taharah  Articles on Acharei Mot-Kedoshim Rabbi Beinish Ginsburg: Torah Sheba'al Peh Rabbi Shmuel Goldin: When Prohibitions Collide Rabbi Meir Goldwicht: The Unique Kedusha of Am Yisrael Rabbi Avraham Gordimer: Issurei Arayos Rabbi Dovid Gottlieb: Normal Holiness Rabbi Maury Grebenau: This Land is His Land Rabbi Josh Hoffman: How Strange Rabbi David Horwitz: Nahmanides on the Prohibition to Eat Blood Rabbis Stanley Wagner and Israel Drazin: Onkelos and the Masoretic Tradition Rabbi Avigdor Nebenzahl: Yom Kippur, Atonement, and Matan Torah  Rabbi Jeremy Wieder: Laining for Parshat Acharei Mot-Kedoshim See all shiurim on YUTorah for Parshat Acharei Mot-KedoshimFor Israel: Rabbi Jeremy Wieder: Laining for Parshat Emor See all shiurim on YUTorah for Parshat Emor

New This Week The Halakhic Status and Role of the Government of Israel: Rav Kook, The Rav and a Modern Midrash  Rabbi Saul Berman Kavod Habriot  Rabbi Daniel Z. Feldman Birchos Hanehenin on Fruits and Vegetables  Rabbi Eliakim Koenigsberg Sefer Tanya on Why We Learn Torah  Rabbi Aryeh Leibowitz Halachos of Making Shabbos Early  Rabbi Uri Orlian How to Prepare A Shiur: Tanakh and Halakha  Mrs. Nechama Price Sefirah and Avelut: From Ancient Times to the State of Israel  Rabbi Dr. Jacob J Schacter End of Life and Kriyah  Rabbi Ezra Schwartz The Nature of Mechila in Kibud Av V'em  Rabbi Eliav Silverman Shnei Mikrah V'Echad Targum (part 1)  Rabbi Baruch Simon The Meaning of Zachor, Shamor, Kavod and Oneg Shabbos  Rabbi Zvi Sobolofsky If You Love It, Share It: Concern for the Spiritual Welfare of Our Fellow Jews Rabbi Moshe Tzvi Weinberg

posts so far for Acharei Mos

2012

1. Acharei Mot sources -- further developed.

2. YUTorah on parshas Acharei Mos.

3. Is marrying two sisters intrinsically or extrinsically obnoxious? We consider the perspective of Rashi (intrinsically), Ibn Ezra (based on the land), and Ibn Caspi (who rejects Ibn Ezra and gives a rationalist reason for the prohibition). I suggest that it is extrinsically bad, based on intent and social mores.

2011

1. Achrei Mos sources -- further expanded.
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2. Is there a vav in וְעַל הַכֹּהֲנִים? Yes and no. Is there some way of deciding between these competing masorahs?
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3. The trup on הַשֹּׁכֵן אִתָּם בְּתוֹךְ טֻמְאֹתָם -- The difference between our masorah in trup and that of the Teimanim. In this instance, there is no practical difference, according to the rules as explained by Wickes.
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4. Was Ibn Ezra killed by demons?  So goes the story, showing how Ibn Ezra got his comeuppance, after claiming that demons did not exist. Though whether he actually claimed this is uncertain. I don't really believe the story, though.
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5. Et zachar vs. Ve'et zachar --  Another analysis of the absence or presence of a leading vav. In this instance, our Masoretic text is supported by the Samaritan text.
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6. YUTorah on parashat Acharei Mot.

2010

1. Achrei Mot sources -- revamped, with over 100 meforshim on the parasha and the haftara, organized by sections, such as Rashi's supercommentators.
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2. What are 'their statutes'? Further thoughts -- Further thoughts on what was meant by the statutes we are not meant to follow, in parashat Acharei Mot. I consider the idea of mandated mariages, as well of prohibited marriages. In particular, if the places they left and they places they went also defined prohibited relations, but differently that Biblical law, one might be prone to thinking of Biblically prohibited relations as not true incest. Therefore, the instruction not to follow intheir statutes, but in our own.
   .
3. 
   

2009

1. Acharei Mos sources -- links by aliyah and perek to an online Mikraos Gedolos, as well as a slew of meforshim on the parsha and haftara.
2. Why mention that it was after the death of Aharon's two sons? -- and whether on a peshat level there is some connection, more than chronological proximity, between that tragic event and the instructions to the kohanim.
3. What are "their statutes"? In plural, when the only statute seems to be Molech. Shadal suggests positive instructions regarding marrying these Torah-forbidden relatives, in situations akin to yibbum. I suggest an alternative, in which these particular set of relatives are considered fair game, and permitted, within the statutes of different societies.
   
   
4. Did the designated man live out the year? The midrash brought down and expanded by Chizkuni, about how he did not, and how they therefore chose someone destined to die anyway that year. And some analysis of how this midrash might have formed.
5. My theory about the runaway scapegoat, and how this could have been a Sadducee trick, year after year, in order to fulfill the Yom Kippur ritual in accordance with their own interpretation. And the text of the Yerushalmi I am basing this theory on.
6. You can also check out DovBear's extensive blogging this year about the goat to Azazel.

2008

• Goral LaAzazel
• Two issues: It looks like idolatry, and why do we push it off a cliff when the pasuk says to send it into the wilderness? Rashi, Shadal, and Aharon ben Yosef solve this in their own ways.

2005

1. The Goat to Azazel
• may look like syncretism, but it really is sending it off to a place. Compare with the next perek which requires bringing sacrifices to the Ohel Moed as opposed to the demons of the field. A comparison to the birds of the metzorah. And a possible Sadducee trick of "losing" the goat in the wilderness before being able to push it off the cliff.
2. דמו בנפשו
• and how Ibn Ezra's comment on this verse is not evidence of ruach hakodesh showing knowledge of oxygenated vs. non-oxygenated blood. An excerpt:
  
  
  
  
  

  He noted that this commentary by Ibn Ezra seems to recognize a modern medical fact - that there is a dual circulation , one of oxygenated blood (blood carrying oxygen, the oxygen obtained from the lungs) and unoxygenated blood. Further, as we know, the oxygenated blood is pumped out of the left side of the heart, and the unoxygenated blood comes in to the right side of the heart. Ibn Ezra thus seems to know of arteries, which carry oxygenated blood, and veins, carrying unoxygenated blood.
  
  This would be astounding, for Ibn Ezra was born in 1092 and passed on in 1167, and it was only in 1628 that William Harvey suggested the modern model.

  I show why this assertion is incorrect.
3. Speak, Speak
• But say what?
  
  
  
  

  The problem is that we have the first pasuk saying that Hashem spoke to Moshe, but we are not told what He said. The second verse says that Hashem spoke to Moshe and states the contents of Hashem's speech.

  Two midrashic explanations, and then attempts at peshat explanations.

2004

1. BeDibur Echad: (this includes reference to the issur Bamot in parashat Acharei Mot and a related, slightly opposing laws in sefer Devarim)
   Different accounts, different perspectives
2. A link to an Opinion Journal article: "These United States - Will same-sex marriage lead to incest and polygamy? Let's hope so!"
3. Nadav and Avihu vs. Korach's Edah (also see posts on parshat Shemini on this)
1. How the descriptions of act and death are similar, so perhaps the sin is similar. Yet the midrash directly contradicts this presumption. And how it does so.
4. Seirim: post I, post II, post III.
1. What were they and what were their role in the Israelite mind. In retrospect, I could have done these better...
5. to be continued

How many legs does a מַרְבֵּה רַגְלַיִם have?

How many legs
does this centipede have?

Summary: Rashi in parashas Shemini says it is called centipede, and they call it '100 legs'. But of course centipedes have less than this, so lav davka. Still, could it have 32 legs, as Torah Temimah describes?

Post: Towards the end of parashat Shemini, we encounter the following pasuk and Rashi:

42. Any [creature] that goes on its belly, and any [creature] that walks on four [legs] to any [creature] that has many legs, among all creeping creatures that creep on the ground, you shall not eat, for they are an abomination.

מב. כֹּל הוֹלֵךְ עַל גָּחוֹן וְכֹל הוֹלֵךְ עַל אַרְבַּע עַד כָּל מַרְבֵּה רַגְלַיִם לְכָל הַשֶּׁרֶץ הַשֹּׁרֵץ עַל הָאָרֶץ לֹא תֹאכְלוּם כִּי שֶׁקֶץ הֵם:

any [creature] that has many legs: This is the centipede, a creature with legs from its head to its tail, on either side, called centipede [in French]. — [Torath Kohanim 11:163]

מרבה רגלים: זה נדל שרץ שיש לו רגלים מראשו ועד זנבו לכאן ולכאן, וקורין ציינפיי"ש [נדל]:

The association with the נדל is in Toras Kohanim, that is Sifra, over here. But the description and the identification of the נדל as centipede is from Rashi.

Though Rashi does not say so explicitly here, centipede means 100 legs. However, in Chullin, 3rd perek, in the sugya of nesher, Rashi does say that they call the נדל meah raglayim.

In Ateres HaMikra, by R' Shmuel Goldshmidt, we find the following fascinating discussion brought down. After citing Rashi, with an explanation of centipede as 100 legs:

Torah Temima: Not precisely 100, but the intent is many.

Tosefes Bracha:  But in truth, this sheretz has only 32 legs to a male and 34 to a female.

The author of both Torah Temima and Tosefes Bracha is R' Baruch Epstein. Here is the text of Torah Temimah:

I did not have the opportunity to do much research, to be able to determine if there is a species of centipede where the male has a different number of legs than the female. But Wikipedia has the following about centipedes (if we are to believe Wikipedia -- but it supports it with two citations):

Despite the name, centipedes can have a varying number of legs from under 20 to over 300. Centipedes have an odd number of pairs of legs, e.g. 15 or 17 pairs of legs (30 or 34 legs) but never 16 pairs (32 legs).

If so, it does not seem that male centipedes could have 32 legs. However, Wikipedia and other sources do not say this about millipedes. So the Tosefes Beracha could have been talking about a specific species of millipede. I wonder at what point millipedes were historically distinguished from centipedes.

Acharei Mos sources -- 2012 edition

by aliyah

rishon (16:1)

sheni (16:18)

shlishi (16:25)

revii (17:1)

chamishi (17:8)

shishi (18:6) 

shevii (18:22)

maftir (18:28)

haftara (Yechezkel 22)

by perek

perek 16 ; perek 17 ; perek 18

meforshim

Judaica Press Rashi in English and Hebrew (France, 1040 - 1105) -- ואני לא באתי אלא לפשוטו של מקרא ולאגדה המיישבת דברי המקרא, דבר דבור על אופניו

Shadal (1800-1865) -- see Wikipedia entry:

1. In plain text  here , though not encoding some of the trup and nikkud, and omitting certain references to non-Jewish scholars.
2. In Google book form    here , but with all that was omitted above. Also, with Shadal's Italian translation of the Chumash text.
3. Mishtadel, an earlier and shorter commentary
4. In determining the correct girsa of Targum Onkelos, Ohev Ger

Chizkuni

Daat -- with Rashi, Ramban, Seforno, Ibn Ezra, Rashbam, Rabbenu Bachya, Midrash Rabba, Tanchuma+, Lekach Tov, Yalkut Shimoni, Gilyonot.

Gilyonot Nechama Leibovitz (Hebrew)  -- see Wikipedia

Rav Yonasan Eibeshitz (1690-1764) -- see Wikipedia entry:

1. Tiferes Yehonasan
2. Chasdei Yehonasan  -- chiddushim and pilpulim on midrashim, Toras Kohanim, Sifrei, and Rashi al haTorah. With supercommentary of R' Yaakov Goldshlag.
3. Toldos Yitzchak Acharon, repeated from Rav Yonasan Eibeshitz -- not until Kedoshim
4. Divrei Yehonasan -- discussing halacha and aggada together, interpreting difficult midrashim
5. Nefesh Yehonasan -- commentary on midrashim and pilpulim + Tanchuma, and suygot in Shas connected to each parsha.
6. Midrash Yehonasan -- on difficult midrashim

Metzora sources -- 2012 edition

by aliyah

rishon (14:1)

sheni (14:13)

shlishi (14:21)

revii (14:33)

chamishi (14:54)

shishi (15:16)

shevii (15:29), maftir (15:31)

haftara (II Melachim 7:3) -- four lepers

by perek

perek 14 ; perek 15

meforshim

Judaica Press Rashi in English and Hebrew (France, 1040 - 1105) -- ואני לא באתי אלא לפשוטו של מקרא ולאגדה המיישבת דברי המקרא, דבר דבור על אופניו

Shadal (1800-1865) -- see Wikipedia entry:

1. In plain text  here , though not encoding some of the trup and nikkud, and omitting certain references to non-Jewish scholars.
2. In Google book form here , but with all that was omitted above. Also, with Shadal's Italian translation of the Chumash text.
3. Mishtadel, an earlier and shorter commentary
4. In determining the correct girsa of Targum Onkelos,  Ohev Ger

Daat -- with Rashi, Ramban, Seforno, Ibn Ezra, Rashbam, Rabbenu Bachya, Midrash Rabba, Tanchuma+, Lekach Tov, Yalkut Shimoni, Gilyonot.

Gilyonot Nechama Leibovitz (Hebrew) -- see Wikipedia

Rav Yonasan Eibeshitz (1690-1764) -- see Wikipedia entry:

1. Tiferes Yehonasan
2. Chasdei Yehonasan  -- chiddushim and pilpulim on midrashim, Toras Kohanim, Sifrei, and Rashi al haTorah. With supercommentary of R' Yaakov Goldshlag.
3. Toldos Yitzchak Acharon, repeated from Rav Yonasan Eibeshitz -- not until Kedoshim
4. Divrei Yehonasan   -- not until Acharei Mos -- discussing halacha and aggada together, interpreting difficult midrashim
5. Nefesh Yehonasan  -- commentary on midrashim and pilpulim + Tanchuma, and suygot in Shas connected to each parsha.
6. Midrash Yehonasan  -- on difficult midrashim

Even Shleimah -- from Rabbi Shlomo Zalman Ehrenreich

R' Saadia Gaon(882-942) -- see Wikipedia entry:

1. Arabic translation of Torah,  here  at Temanim.org. This is a beautiful PDF, with the Chumash text, Rashi, Onkelos, and Rav Saadia's Tafsir. All of these have nikkud, which is a very nice feature. It also designates the Temani and standard aliyah breaks, and two commentaries, Shemen HaMor and Chelek HaDikduk, on the kriyah, trup, nikkud, and dikduk, on the basis of Yemenite manuscripts, which would be worthwhile even absent the other features. Quite excellent, overall.
2. The same Arabic translation, the Tafsir,  here at Google books. No nikkud, Chumash text, Rashi, or Onkelos. But there is a brief supercommentary by Yosef Direnburg at the bottom of each page. 
3. Collected commentary of Saadia Gaon on Torah , selected from the writings of various Rishonim and from his commentaries on other works. 

posts so far for parashat Tazria

2012

1. Tazria sources, 2012 edition. Further expanded.

2. Rav Mordechai Gifter on Isha Ki Tazria -- The Ramban gives two explanations of isha ki tazria, one according to Aristotle and the other according to Galen. Are they both simultaneously true, on some plane? And does this solve all our problems of Torah seeming to contradict science?

3. Why does ואת עמלני refers to sons specifically?
 Rav Chaim Kanievsky explains, based on a gemara that רוצה לעשות כל בניו זכרים יבעול וישנה, which entails greater tircha. And this is related to the beginning of parashat Tazria, and the famous derasha about how to have male children.

4. YUTorah on parashat Tazria.

5. Chess in Rabbinic sources -- "Ibn Ezra wrote the following poetic riddle about the game of Chess. {J: ishkaki / shach-mat = Check Mate."


2011

1. Tazria sources -- further improved. For example, many more meforshei Rashi.
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2. YU Torah on parshat Tazria.
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3. Why no 'famous' derasha on Isha Ki Tazria? Maybe there is. Regardless, what about the law of conservation of derashot?
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4. Why does Rashi explain the pasuk of וּבְיוֹם הֵרָאוֹת בּוֹ בָּשָׂר חַי יִטְמָא out of order? Bartenura gives his answer; I give my own, that maybe it is not out of order, and if it is, it is a logical order.
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5. A Taz I can agree with --   About revisiting the midrashei halacha Rashi is merely citing, and whether we are skilled enough to do it.
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6. Why is וְכִבַּסְתֶּם translated as וּתְחַוְּרוּן?  Onkelos strays from his usual path. Is this a violation of the rule laid down by Rashi in parshat Tazria?

2010

1. Tazria sources -- expanded
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2. All about Chazal and contemporary science. First, How did Chazal know that 'drop exudes from the brain and develops into semen'? A better question, IMHO, is how the Pythagoreans knew. Before kvetching and reinterpreting to make Chazal know this with ruach hakodesh, why not check to see if ancient science, contemporary to Chazal, asserted precisely the same thing?
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3. Next, How did Chazal know that hemophilia is transmitted by the mother's DNA? With what I think is a good answer.

2009

1. Tazria sources -- links by aliyah and perek to an online Mikraos Gedolos, and links to many meforshim on the parshah and haftarah.
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2. The famous midrash of Isha Ki Tazria; who promotes and who rejects the midrash (at least as peshat); and thought about the motivations for this midrash.
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3. As an alternative to the advice in the aforementioned famous midrash, Chizkuni offers other reproductive advice on how to have male children, based on contemporary science. And how he reads this into, or out of, a pasuk in Shir HaShirim.

2008

• Dam Tohar
• and various unsuccessful and successful attempts to uproot this halachic entity declared by the Torah and Chazal.

2006

• Tekiat Shofar and Sisera's mother
• Where parshat Tazria factors in in that a midrash there states that a woman wails and cries out 100 times when giving birth, with possible parallels to the custom of 100 shofar blasts.

2004

• Isha Ki Tazria and Sex Selection Theory

• An updated account of the midrash that if a woman is tazria first (before the man), she has a boy (isha ki tazria veyalda zachar.) The original midrash operated under the assumption that she gave forth this seed on orgasm. But there is a debated theory that if a woman ovulates before coitus, she is more likely to have male offspring, but if coitus happens before ovulation, she is more likely to have female offspring, on the basis of endurance vs. speed of the two types of sperm. This is debated for humans, but is a known matter for several animal species. A link to some of the research, plus pictures of some of the animals for which this is true.

to be continued...

Rav Mordechai Gifter on Isha Ki Tazria

Summary: The Ramban gives two explanations of isha ki tazria, one according to Aristotle and the other according to Galen. Are they both simultaneously true, on some plane? And does this solve all our problems of Torah seeming to contradict science?

Post: Parashat Tazria begins:

2. Speak to the children of Israel, saying: If a woman conceives and gives birth to a male, she shall be unclean for seven days; as [in] the days of her menstrual flow, she shall be unclean.

ב. דַּבֵּר אֶל בְּנֵי יִשְׂרָאֵל לֵאמֹר אִשָּׁה כִּי תַזְרִיעַ וְיָלְדָה זָכָר וְטָמְאָה שִׁבְעַת יָמִים כִּימֵי נִדַּת דְּוֹתָהּ תִּטְמָא:

And the Ramban discusses the famous derasha of Chazal:

ובמשמעותו אמרו (נדה לא א): ש

אשה כי תזריע, אשה מזרעת תחילה יולדת זכר. 

ואין כוונתם שיעשה הולד מזרע האשה, כי האשה אע"פ שיש לה ביצים כביצי זכר, או שלא יעשה בהן זרע כלל, או שאין הזרע ההוא נקפא ולא עושה דבר בעובר, אבל אמרם "מזרעת", על דם הרחם שיתאסף בשעת גמר ביאה באם ומתאחז בזרע הזכר, כי לדעתם הולד נוצר מדם הנקבה ומלובן האיש, ולשניהם יקראו זרע.  ש

וכך אמרו (שם):  ש 

שלושה שותפין יש בו באדם, איש מזריע בו לובן שממנו גידים ועצמות ולובן שבעין, אשה מזרעת אודם שממנו עור ובשר ודם ושער ושחור שבעין. 

ש וגם דעת הרופאים ביצירה כך היא. ש

ועל דעת פילוסופי היונים:  ש 

כל גוף העובר מדם האשה, אין בו לאיש אלא הכח הידוע בלשונם היולי שהוא נותן צורה בחומר, כי אין בין ביצת התרנגולת הבאה מן הזכר לנולדת מן המתפלשת בעפר שום הפרש, וזו תגדל אפרוח וזו לא תזרע ולא תצמיח, בהמנע ממנה החום היסודי שהוא לה היולי. 

ואם כן יהיה מלת תזריע כמו זרועיה תצמיח (ישעיה סא יא).  ש

וכן אמר אונקלוס:  ש 

ארי תעדי.

I'll only translate the beginning of it:

"And regarding its implication they wrote (Niddah 31a):

אִשָּׁה כִּי תַזְרִיעַ -- 'if a woman gives seed first, she will give birth to a male.' 

And their intent was not that the child would be made from the seed of the woman, for the woman, though she has eggs like the eggs of a male, either no seed at all is made from them, or that seed has no impact in the fetus. But what they said 'gives seed', they are referring to the blood of the womb which collects at the end of completion of intercourse in the mother, and seizes upon the seed of the male, for in their opinion, the fetus is fashioned from the blood of the female and the white material of the man, and to both of them {blood and white material} is called zera.


And so did they say (there):

There are three partners in a human being -- the man gives forth white seed, from which are fashioned sinews, bones, and the whites of the eyes, and the woman gives forth the red material, from which are fashioned the skin, flesh, blood, hair, and the black of the eye.

And so too is the position of the doctors of gestation.


And based on the position of the Greek philosophers:

The entire body of the fetus is from the blood of the woman, and the only contribution of the man is the force known in their language {Greek} as hyuli, which gives form {tzura} to the substance {chomer}, for there there is not between a chicken egg which came from {the hen after intercourse with} the male, and a chicken egg from {a hen which} was excited by the ground, yet this one will develop into a chick while this one will not have seed and will not flourish, since the primal heat called hyuli was kept from it.

And if so, the word tazria is like {Yeshaya 61:11} '[as a garden that] sprouts forth its seedlings'. And so does Onkelos say, ארי תעדי."

We see here a dispute between the Greek philosophers and Chazal. Likely Chazal in turn relied on other own non-Jewish scientists, for instance, Galen:

 For in the treatise On Seed, it was shown that most parts of the body arise from seed, with the fleshy parts alone formed from blood.

We see Ramban willing to find Scriptural support for either position, and that he is willing to consider the possibility that Chazal were wrong on this scientific matter. This is an important observation in its own right.

And we also know that both of these positions, of Chazal (and scientists) and of the Greek philosophers are not scientifically correct. (The form is determined by the DNA from both of them, and the body of the fetus is from a single fertilized egg from the woman (combined with a single sperm cell from the man), not from the blood.

Rav Mordechai Gifter, in Pirkei Torah, wrote:

"In all matters of the science of nature which Chazal said which contradict the words of the scholars of nature, such as that worms which grow from the cheese itself {Josh: via spontaneous generation}are not forbidden, while according to what is known about nature, there is no such thing that it spontaneously generates from itself (but rather it is formed via other things which come from outside, and others like this). But there are here two different approaches. For the Torah law was stated according to what the chush {senses, instinct} could recognize in this matter, and not according to the knowledge of chochma{lit. wisdom, science}, and there is no contradiction at all.


And I heard from a certain Gadol that this explains the distinction between shav and sheker. For anyone who changes from that which is known via chush is shav, while {one who changes from} that known by chochma {science, wisdom} is only sheker and not shav. 


And behold, the intent of the Ramban here are that the words of the gentile scholars are correct by virtue of their seeing this in the nature of the things, that according to their observation, the father gives the force of the hyuli, but according to what Chazal saw in this with the viewing of the Torah, there is in the giving from the father an aspect of the giving of the white of the sinews and bones, and from the point of the observation of science, this as well is found in the words of the holy Torah -- and there is not here a matter of contradiction between truth and falsehood. And understand this, for it touches upon quite a number of matters of faith."

An interesting idea, and one which harmonizes the two points brought up by the Ramban. Though saying that both are true across different paths (גישות) in this instance of isha ki tazria might not leave a path for the third view, namely modern science, which contradicts both of these. (And Rav Gifter would have known of modern science.) Of course, we can say that Ramban was wrong in his endorsement of Greek philosophy as one of those two paths, and let modern science take its place in the secondary path.

This approach allows Torah to diverge in all instances from what is actually true in the observable world, since it functions on a separate plane, that of "chush". And this might be taken to apply to modern practical halachic questions, rather than just hashkafic questions. For example, the anisakis worm.

I don't know that I agree with this approach, however. I don't think Chazal thought that they were operating on a different plane. They thought there was just a single reality. And that is why they consulted medical experts, occasionally conducted experiments, and so on and so forth.

What I think is happening in this particular instance is that there was a divergence in Greek medicine.

1. Aristotle put forth the idea of chomer and tzura:  "Aristotle claimed that form (eidos, morphe] inheres in or is "immersed" in matter (hyle)" . Thus, this falls under Greek philosophy, and medicine as influenced by Greek philosophy. Aristotle writes " "It follows that what the female would contribute to the semen of the male would be material for the semen to work upon." In other words the semen clots the menstrual blood."
2. Galen (and I think Hippocrates) put forth the idea of red and white seed forming different parts of the baby. This was adopted by Chazal. And it was also the contemporary medical belief at the time of the Ramban, presumably via Avicenna. 

Meanwhile, there was other theories which developed across time. Here is an interesting article, as it touches upon Islamic belief. 

Ramban didn't mention both for both of them to be correct. He thought either one was plausible, and (in his day) impossible to determine. So he showed how either could be worked into the pesukim. But one of them is still incorrect.