While modern technology has few ancient parallels, its underlying mechanical concepts often do. As we look back at Talmudic dialogue to appropriately apply it to today’s dramatically different context, one particular debate between the Academies of Shammai and Hillel stands out as crucial.
Machines acting on their own accord, based on mere human instruction, did not exist in Talmudic times. However, if we break down the issue into its components, we can find analogues. When discussing robots, which may not yet have reached Asimov’s vision but are still quite advanced, there are two main issues — the instruction and the action.
The first regards how we command a robot. Is merely telling a robot to perform a melakhah (forbidden action) allowed? The Talmud (Bava Metzi’a 90b and elsewhere) debates whether speech is considered an action. Only a person who performs a forbidden act may be punished with lashes. Does cursing God, for example, constitute an action? One suggestion is that the movement of lips is an action. Tosafos (ad loc., sv. Rabbi Yochanan) conclude that only speech that leads to commission of an act is considered also an act. If we accept this ruling as conclusive, then ordering a robot to perform a melakhah can be considered, all other things equal, a forbidden act. Additionally, since this is the normal way of commanding a robot, according to may authorities it is a direct, and not indirect, action (see this post).
Indeed, when halakhic authorities discussed the status of telephones, microphones and hearing aids, they assumed that speech that causes electricity to flow is potentially forbidden. R. Shlomo Zalman Auerbach, according to one report, considered thought that directs a forbidden labor, such as via machines that read brain waves, to be forbidden (Me’orei Eish Ha-Shalem 10:13 pp. 765-766; pp. 893-895).
Therefore, if we assume that a robot’s electrical movement is at least forbidden rabbinically, ordering a robot to move or function in any way is also forbidden. But this only refers to commanding a robot on Shabbos to act on Shabbos. What about instructing the robot before Shabbos? The Sages (Shabbos 19a) forbade asking a gentile before Shabbos to perform forbidden labors on Shabbos except under specific examples. The concept of the “Shabbos Goy,” a gentile who performs labor for Jews, is highly limited. Yet, since robots did not exist in Talmudic times, one would be hard pressed to claim they fall under the rabbinic prohibition. Rather, the aforementioned debate between the Academies of Shammai and Hillel provide a more compelling precedent.
While the biblical prohibition of performing melakhah only applies on Shabbos, it applies to more than just the Jew himself. A Jew is obligated to ensure that his entire household — including his servants and animals — observe Shabbos. What about his utensils and appliances? Can he lend his lawnmower to his gentile friend to use on Shabbos?
The Mishnah (Shabbos 17b-18a) lists a number of such actions that, according to Beis Shammai, are forbidden on Shabbos while according to Beis Hillel are permitted. Beis Shammai forbids you to start a melakhah on Friday afternoon that will continue on Shabbos but Beis Hillel permits. The Gemara (ibid., 18a) quotes a Baraisa that permits opening an irrigation tunnel that will water a garden on Shabbos but forbids placing wheat on a water-driven grinding mill that will grind it on Shabbos. The Gemara contains three ways of understanding the debate between Beis Shammai and Beis Hillel, and the Baraisa:
- Rabbah: Beis Shammai forbids all such actions (for whatever reason) and Beis Hillel permits them all except for grinding wheat in a mill. Beis Hillel forbids the latter, and anything like it, because it generates noise. Rashi (18a sv. she-yetachanu) explains that the noise is a disgrace to Shabbos.
- Rav Yosef: Beis Shammai requires that you rest your appliances on Shabbos and therefore forbids any melakhah done with your utensils on Shabbos. Beis Hillel forbids only active violations, such as the mill grinding wheat, but permits water to flow while a person’s appliances do nothing.
- Rav Oshia: Beis Shammaai forbids any melakhah performed by your utensils and Beis Hillel permits them all, including grinding wheat.
IV. Three Approaches
This is based on a simple, perhaps overly simple, explanation of the Gemara. Medieval authorities reach any of the following three conclusions from this Gemara:
- There is no issue at all with allowing your appliances to function on Shabbos, even if they make noise (i.e. Beis Hillel according to #3 above). (Rabbenu Tam and Rambam)
- The only potential problem with your appliances working on Shabbos is noise (Beis Hillel according to #1 above). (Tosafos and Rosh)
- Even according to Rabbah, Beis Hillel forbids you to allow your appliances to actively perform a melakhah but mentions noise to forbid even using a gentile’s mill. (Rokei’ach)
The Shulchan Arukh (Orach Chaim 252:5) rules like #1 above, that there is no problem when your appliances perform melakhah on Shabbos, even if they generate noise. The Rema (ibid.) rules like #2 above, allowing for exceptions in the case of loss. The Bach (ibid., 246:2) suggests that a God-fearing person will follow #3.
Applying this to contemporary technology, the Rema would insist that you turn off before Shabbos any appliance that will make noise. Exactly what constitutes making noise is subject to debate, but authorities have used this reason to forbid leaving a radio or television running on Shabbos, or turning on by a timer (e.g. Yesodei Yeshurun, vol. 3 p. 50).
The Bach would be stricter. He would insist you turn off all appliances before Shabbos. R. Shlomo Zalman Auerbach (Me’orei Eish ch. 4 sec. 6=Shulchan Shlomo, Shabbos 246:1) rules according to the Bach. However, rather than turning appliances off, he suggests rendering them ownerless (hefker) before Shabbos. My sense is that this is a minority view. R. Nosson Gestetner (Le-Horos Nasan, vol. 8 no. 13) explicitly rejects this approach and R. Simcha Rabinowitz (Piskei Teshuvos vol. 7 ch. 246 n. 1) states that he is unaware of a contemporary who agrees with R. Auerbach’s rulling. [However, see here: link]
V. New Technologies
This issue applies to a number of technological developments of the past century. Not just timers, which are older, but vending machines (see Minchas Yitzchak, vol. 3 no. 34; She’arim Metzuyanim Ba-Halakhah 80:63), answering machines (see Shevet Ha-Levi, vol. 5 no. 28) and web servers (see Or Yisrael 35, Nissan 5764, pp. 17-54). Are you allowed to let them function on Shabbos or not? There are other considerations but regarding the basic rule of your appliance working on Shabbos, the above three-way debate would seem to apply.
Similarly, the Shulchan Arukh would allow a Jew’s robot to act on its own initiative on Shabbos (although this view might be stricter than I am presenting it — see Iggeros Moshe, Orach Chaim vol. 3 55:1; Yabi’a Omer vol. 1 20:12, vol. 3 17:6-7). The Rema would forbid it from moving or acting in any way that causes significant noise. And the Bach would forbid the robot to move at all, unless its Jewish owner relinquished ownership before Shabbos.
As mentioned, there are other considerations involved, many of which R. J. David Bleich discusses in his Contemporary Halakhic Problems, vol. 5 ch. 5. Perhaps most significant is the meta-halakhic issue raised by R. Moshe Feinstein (Iggeros Moshe, Orach Chaim vol. 4 no. 60) regarding timers, that they could effectively undermine all the Shabbos rules, thereby disgracing the day. While most authorities disagreed with R. Feinstein’s application to timers, the concept may still be effectively applied to robots. When and if they become commonplace, halakhic authorities will have to decide whether the idea is sufficient to forbid their use on Shabbos.