Q&A: Killing a Louse on the Sabbath
Killing a Louse on the Sabbath
Question
Regarding killing a louse on the Sabbath, what does the Rabbi think about the reasoning that the Torah is measured by sensory perception, and whatever we found with a microscope makes no difference?
By the way, this won’t help as a general solution to problems of this kind. For example, a woman who gave birth within the last three days: the Sages forbade her to fast even if she and the doctors say she can fast. And today doctors say that this is not necessarily dangerous. (Assuming that is true; I came across it through an internet search.) Here it seems to me that the reasoning based on sensory perception would not help.
Answer
A louse is visible to the naked eye.
As for dangers, the question of what is visible and what is not is not important. That is a factual question: is there danger or is there not? Even if the danger is caused by something not visible to the eye (and there are many such cases), it is still danger in every respect. And regarding a woman after childbirth, where the Sages said there is danger and medicine today says there is not—this has nothing at all to do with the question of what is visible or not visible. It is apparently a medical error on the part of the Sages (assuming that medicine today really says so. I have not checked).
By the way, one can also define this. If something not visible to the eye has consequences that are visible to the eye, then it is treated like something that is visible. An analogy would be the labor of building with an electrical device. What happens in the circuits is not visible to the eye, but the operation of the device is a consequence visible to the eye. Something similar appears in the dispute between Rabbi Akiva Eiger and the Shitah Mekubetzet in Nazir 11 (see Kovetz Shiurim there) regarding a nazirite vow made conditionally—whether this is speech that uproots an act, or speech that uproots speech (because naziriteship is speech, but it has a real-world consequence—the taking effect of naziriteship).
As for the reasoning itself, it comes up in several contexts (such as the prohibition against eating worms and the like), and in my view it definitely has a place.
Sometimes, however, people present this as casting aspersions on the earlier generations, who lived without microscopes and violated the prohibition. In my view that consideration is irrelevant, since they did the best they could and we will do the best we can. There is no aspersion here. Sometimes, though, they present it differently: they argue that it is unreasonable for this to be prohibited, because a prohibition is supposed to be eternal, and if earlier generations could not observe it, then apparently it was never prohibited. That is a different line of reasoning, and in my opinion it has merit.
Discussion on Answer
That doesn’t seem significant to me. Usually we do not see reproduction, neither in humans nor in animals. As stated, the result is visible to the eye.
You can see louse eggs. (The Talmud says that the expression “God sustains even the eggs of lice” refers to a different creature.)
With God’s help, eve of the holy Sabbath, Vayelekh, 5779
The reasoning is that the reproduction of lice, which cannot be seen with the naked eye, does not give them the halakhic status of a “creature that reproduces.”
(I seem to recall seeing a similar argument—apparently in Shemirat Shabbat KeHilchatah in the name of Rabbi Shlomo Zalman Auerbach—regarding aphids: since their movement cannot be seen with the naked eye, they are not considered a crawling creature. In the end, however, he concluded that with close observation one can detect their movement even with the naked eye.)
In a responsum on the topic of “Killing Lice on the Sabbath” on the Breslev City site, he showed that the Sages were familiar with louse eggs and nevertheless permitted killing them on the Sabbath. He brings that although researchers agree that lice come from eggs, it has still not been determined whether they reproduce through male-female mating, and there are differing opinions among researchers on this. It may be that, from the standpoint of Jewish law, a creature is considered to “reproduce” only when it comes from male and female, and the matter requires clarification.
May we merit fruitfulness and multiplication in Torah and wisdom, and He who hangs the earth upon nothingness should grant us a good sealing, for a year of salvation and consolation, as blessed by S. Tz. Levinger.
In the article “Managing on Their Own: Research Findings Are Mentioned in the Talmud” (on the Hidabroot website), it is mentioned that there is a species of lice called “chewing lice” in which no males have been observed at all, and it is assumed that they reproduce by parthenogenesis. He suggests that this is what the Sages meant by “they do not reproduce.” He notes that the Sages in tractate Gittin also mentioned “lice that come from male and female.”
It should be noted, according to his words, that today it appears that head lice are among those that “come from male and female,” and apparently it would therefore be forbidden to kill them; whereas in the time of the Sages, the lice that reproduced by parthenogenesis were common even on human heads, which is not common today.
With blessings, S. Tz. Levinger
S. Tz. Levinger,
Parthenogenesis too is reproduction for purposes of the labor of taking life, since the emphasis is only on the fact that the louse comes into being from sweat. Some of the medieval authorities even wrote that a flea, which comes into being from dust and not from sweat, is forbidden to kill, because only something generated from sweat is not considered alive in this respect.
Also, from the Talmud itself you can see this, because it asks: how can it be that the Holy One, blessed be He, sustains “from louse eggs to the horns of wild oxen”? If a louse does not reproduce, where do the eggs come from? And it is forced to answer that “louse eggs” is the name of a species of louse. Why didn’t the Talmud answer that it was referring to parthenogenesis, in which there are eggs? Clearly, then, the Talmud did not distinguish between sexual reproduction and parthenogenesis, and treated both as reproduction in every respect.
Head lice and pubic lice are parasites of the human species. Delousing is part of our simian heritage, which perhaps explains why it imparts an evil spirit requiring hand-washing. It may be that because lice are our parasites and cannot exist separately from us, they were perceived by the halakhic decisors as part of human filth. From there, the road to seeing them as creatures that reproduce from sweat rather than through “be fruitful and multiply” is short. Practically speaking, one can simply throw them outside and not drown them in the toilet, if only because of the concern that in practice they do have independent status.
The claim is that its reproduction is not visible to the naked eye (I haven’t checked).