Maternal Impressions: From Sheep to Humans
After working for his father in-law Laban fourteen years for his two wives Rachel and Leah, Jacob wishes to return home. Laban asks him what it would cost for him to stay on as a shepherd for his flocks, Jacob responds that the sheep be divided. All the white sheep would go to Laban but all the spotted and speckled sheep would go to Jacob.
Laban, crafty as always, agrees to this but, in order to stack the deck in his favor, immediately takes all the spotted and speckled sheep in the flock and hands them over to his sons to watch in a field three days travel away from the rest of the flock under Jacob’s care. Jacob is then, effectively, given a flock that is 100% pure white, lowering the chances that he could produce spotted and speckled sheep at all. Laban strikes again.
However, Jacob has learned the art of craftiness from his father-in-law and has a plan:
בראשית ל:לז וַיִּקַּח לוֹ יַעֲקֹב מַקַּל לִבְנֶה לַח וְלוּז וְעַרְמוֹן וַיְפַצֵּל בָּהֵן פְּצָלוֹת לְבָנוֹת מַחְשֹׂף הַלָּבָן אֲשֶׁר עַל הַמַּקְלוֹת. ל:לח וַיַּצֵּג אֶת הַמַּקְלוֹת אֲשֶׁר פִּצֵּל בָּרֳהָטִים בְּשִׁקֲתוֹת הַמָּיִם אֲשֶׁר תָּבֹאןָ הַצֹּאן לִשְׁתּוֹת לְנֹכַח הַצֹּאן וַיֵּחַמְנָה בְּבֹאָן לִשְׁתּוֹת. ל:לט וַיֶּחֱמוּ הַצֹּאן אֶל הַמַּקְלוֹת וַתֵּלַדְןָ הַצֹּאן עֲקֻדִּים נְקֻדִּים וּטְלֻאִים.
Gen 30:37 Jacob then got fresh shoots of poplar, and of almond and plane, and peeled white stripes in them, laying bare the white of the shoots. 30:38 The rods that he had peeled he set up in front of the goats in the troughs, the water receptacles, that the goats came to drink from. 30:39 Their mating occurred when they came to drink, and since the goats mated by the rods, the goats brought forth streaked, speckled, and spotted young.
He takes the brown branches of poplar and almond trees and peels parts of the them to expose the white pulpy material inside. He then stands those branches up before the water troughs, where the sheep mate, and the sheep begin to produce spotted and speckled offspring.
But what was the trick? Rabbeinu Bahya ben Asher offers an explanation (Gen. 30:38).
היתה צורת המקלות שכנגד עיניהן חקוקה מצטיירת בלבם ובמחשבתן בשעת החמום, ומזה היו הנולדים עקודים נקודים
The form of the sticks was before their eyes and carved itself into their minds and thoughts while they were in heat, and because of this they would give birth to speckled and spotted offspring.
According to Rabbeinu Bahya (mid-14th cent.), whatever form is in an animal’s mind when it mates will be the form that the offspring takes as it forms in the womb. He goes on to explain the practical lesson one can learn from this fact.
וממעשה הטבע שבפרשה זו יש ללמוד חיוב בני אדם שיש להם שכל ודעת לקדש עצמם בשעה שנזקקין עם נשותיהם, שהרי אנו רואים בבהמות ציור העובר יוצא כפי ציור המחשבה.
Now from this natural phenomenon that occurs in our parashah we learn the requirement for intelligent creatures to sanctify their minds when they are copulating, for we see that with animals the fetus takes on the form of the parent’s thought.
וע”כ אמרו ז”ל: (שבועות יח ב) לעולם יקדש אדם את עצמו בשעת תשמיש. וקדושה זו היא טהרת המחשבה שלא יחשוב באשה אחרת ולא בדברים אחרים רק באשתו,
For this reason the Sages said (Shevuot 18b): “A man must always sanctify himself during intercourse.” This sanctification refers to purifying one’s mind, so that he does not think about other women or anything else other than his wife.
וזהו ק”ו שאין עליו תשובה: אם הבהמות שאין להם דעה להבין תועלת הדבר ונזקו, ואינן עושות אלא מכח הטבע, יש להם כח לפעול בתולדות כפי הצורה המצטיירת בלבם והקבוע במחשבתם, ק”ו לבני אדם אשר להם כח גדול בנפש השכלית לצייר במחשבתם ובלבם העליונים והתחתונים, ויש להם כונה בדעת ובשכל להתכוין באותו הציור, שצריכים לטהר מחשבותם בענין ההוא.
This is easily demonstrable a fortiori and cannot be refuted: If animals, who have no intelligence to understand the benefit of a matter or its detriment, and only act out of instinct, have the power to mold their offspring according to their thoughts at the time of copulation, how much more so for human beings, how have great power of intellect to form in their minds perceptions of matters lofty and mundane, and they have the power to direct their thoughts with regard to any given matter, that they need to purify their thoughts for this endeavor!
In short, R. Bahya believes that a fetus takes on characteristics of what the father (or mother?) was thinking about during conception. Jacob, aware of this “scientific fact,” used it to his advantage by placing the idea of “spots” and “speckles” into the minds of the mating sheep and goats. This is the interpretation of R. Ovadiah Seforno as well.
The theory with which Jacob was working is a version of an outdated theory called maternal impression. This theory held that what was in the mother’s mind during pregnancy could affect the child in utero. The Torah’s view, and that of the Rabbis, seems to focus specifically on thoughts during conception and not throughout pregnancy. This theory was held by Pliny the Elder (1st cent. CE) as well:
Cases of likeness are indeed an extremely wide subject, and one which includes the belief that a great many accidental circumstances are influential—recollections of sights and sounds and actual sense-impressions received at the time of conception. Also a thought suddenly flitting across the mind of either parent is supposed to produce likeness or to cause a combination of features, and the reason why there are more differences in man than in all the other animals is that his swiftness of thought and quickness of mind and variety of mental character impress a great diversity of patterns, whereas the minds of the other animals are sluggish, and are alike for all and sundry, each in their own kind (Natural History 7:12; Harvard ed.).
Pliny explains here why, in his estimation, human children differ so much from their parents while this is less the case with animals—a claim in keeping with R. Bahya’s a fortiori argument.
This theory leads the Rabbis of the Talmudic period in interesting and surprising directions. For example, the Talmud relates the following anecdote about Rabbi Yochanan (b. Baba Metzia 84a)
רבי יוחנן הוה אזיל ויתיב אשערי טבילה, אמר: כי סלקן בנות ישראל מטבילת מצוה לפגעו בי, כי היכי דלהוו להו בני שפירי כוותי, גמירי אורייתא כוותי.
Rabbi Yochanan would sit before the gates of the ritual bath, he reasoned: “When the Jewish women come out from their ritual emersions, let them see me so that their children will turn out as good looking as I am and as learned in Torah as I am.”
This anecdote is rather shocking. Rabbi Yochanan seems to believe that when the women see him, since he is so good looking, they will be thinking about him when they go home to their husbands and will, luckily for them, produce good-looking and smart children. The premise is that what they think about during conception—in this case Rabbi Yochanan—will affect the appearance of the offspring.
Back to the Jacob story, Genesis Rabbah (VaYetzei 73:10), after explaining Jacob’s trick in the same way as R. Bahya and Seforno, tells this astounding tale:
מעשה בכושי אחד שנשא לכושית אחת והוליד ממנה בן לבן, תפס האב לבן ובא לו אצל ר’ א”ל שמא אינו בני א”ל היה לך מראות בתוך ביתך א”ל הן א”ל שחורה או לבנה א”ל לבנה, א”ל מיכן שהיה לך בן לבן,
It happened once that a colored man married a colored woman and she had a white child. The father took the child to Rabbi [=Yehudah Ha-Nasi] and said: “Maybe this isn’t my son?” [Rabbi] responded: “Do you have portraits in your house?” He said: “Yes.” [Rabbi] asked: “Of black or white [people]?” He said: “White.” [Rabbi] concluded: “This is why you have a white son.”
The same tell, with different characters comes up in Numbers Rabbah (Nasso 9:34) as well, as part of an exposition of the Sotah ritual:
שאל מלך ערביים את רבי עקיבא אני כושי ואשתי כושית וילדה בן לבן אהרגנה שזינתה תחתי אמר לו צורות ביתך שחורות או לבנות אמר לו לבנות אמר לו כשהיית מתעסק עמה נתנה עיניה בצורות הלבנות וילדה כיוצא בהן ואם תמה אתה בדבר למוד מצאנו של יעקב אבינו…
An Arabian king asked Rabbi Akiva: “I am colored and my wife is colored but we had a white son. Should I kill her for cheating on me?” [Rabbi Akiva] said: “Are the idols in your house black or white?” [The king] replied: “White.” [Rabbi Akiva] said: “When you were intimate with her she looked at the white idols and conceived in their likeness. And if such an idea seems surprising to you, learn from the account of our father Jacob…”
Luckily for the king, and even luckier for his wife, Rabbi Akiva did not know that what he suggested is, in fact, scientifically impossible as was Jacob’s trick.
The scientific impossibility of maternal impression theory has not stopped poseqim from using these ideas in complicated paternity cases, especially ones where there is a fear of a child being declared a mamzer (illegitimate/bastard child). Whether or not it works scientifically, maternal impression lives on in halakhic discourse even into modern times.
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Dr. Rabbi Zev Farber is the Senior Editor of TheTorah.com, and a Research Fellow at the Shalom Hartman Institute's Kogod Center. He holds a Ph.D. from Emory University in Jewish Religious Cultures and Hebrew Bible, an M.A. from Hebrew University in Jewish History (biblical period), as well as ordination (yoreh yoreh) and advanced ordination (yadin yadin) from Yeshivat Chovevei Torah (YCT) Rabbinical School. He is the author of Images of Joshua in the Bible and their Reception (De Gruyter 2016) and editor (with Jacob L. Wright) of Archaeology and History of Eighth Century Judah (SBL 2018).
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