Action and Inaction: The Fundamentals of Maaseh in Halacha and Medical Devices

Technological advancements have allowed what was once unimaginable to become a part of our daily routine. Devices that compose the ecosystem of “Smart Homes” are capable of turning on lights, open doors, set thermostats, and much more. While these devices have served to ease our day-to-day routine, similar achievements have drastically improved the lives of those suffering from terrible illnesses rendering them effectively disabled. Paralyzed patients can once again mobilize with the use of robotic limbs. Locked-in syndrome patients can communicate by use of sensors that “read” eye movement. These, among others, have led to fascinating discussions analyzing how does halacha, which requires a person’s involvement to render an action attributed to them, view the use of these technologies?

Importantly, there are two distinct discussions within the broader subject. Foremost, discussed at length by halachic deciders^[1], how do we consider nonspecific action that results in a melachat Shabbat occurring. That is, most Smart Home devices function by sensing the mere presence of the person in the room—the light turns on once the person enters the room, the temperature is set in response to the number of people in the room. Most authorities maintain that which brought the person into proximity of the device is the forbidden action on Shabbat and therefore, walking into the room is prohibited because it resulted in the device’s response.

This was most recently discussed in regards to walking into hospitals on Shabbat during the COVID-19 pandemic where temperatures were automatically taken by sensors built into the front doors. Security guards were responsible for monitoring a computer monitor that aside from displaying whoever walked in front of the camera, would also have text above the image of each person displaying their temperature. In email correspondence, the members of Rabbi Rubin’s Kollel (authors of Orchas Shabbas) argued that it was prohibited to walk into the hospital for several reasons. While previous authorities maintain it is permitted to appear on video display’s primarily because lo neicha li, in this instance there are additional issues due to causing text to appear (the temperature) and allowing one’s temperature to be taken which is a form of measuring on Shabbat.

For these authorities, the act of walking in front of the sensor caused two prohibited actions to occur, writing and measuring. This means they attributed the forbidden action to the walking in front of the sensor. Their position seems to display a fundamental conception of sensors that is not at all obvious. The sensors (especially the one that allows for the temperature to be displayed) are triggered by heat generated by the body, not by movement on the part of the passerby.

The Ralbag in his commentary on Chummush on Parshat Yitro already pointed out that chewing, although arguably a form of grinding, is permitted as the Torah never forbad bodily functions on Shabbat. Similar arguments are utilized by Rabbis Wosner and Bleich in respect to the prohibition of walking in front of sensors. Human heat is simply a normal bodily function, it is difficult to imagine that even if it causes text to appear on a computer screen or measuring of temperature it would be prohibited on Shabbat as no action occurred. More commonly, smart thermostats that respond to the heat generated by the number of people in the room would be permitted on Shabbat.^[2]

Rabbi Ruben Kollel’s argument is also in opposition to Rabbi Feinstein^[3] who argued that taking temperature on Shabbat does not qualify as measuring at all. Significantly, Rabbi Feinstein and Rabbi Bleich both agree that taking temperature on Shabbat is permitted but for two very different reasons. Rabbi Feinstein does not consider measuring temperature to be a type of measuring that matches one of the 39 melachot. Rabbi Bleich however implies that taking temperature is a form of measuring but there is a lack of action as the measuring occurred utilizing a bodily function. The practical application of this distinction is measuring blood pressure on Shabbat for a non-choleh (such as medical school students practicing on each other). According to Rabbi Feinstein, it seems obvious that measuring blood pressure should also not be considered measuring for purposes of hilchot Shabbat and should therefore be permitted. Rabbi Bleich on the other hand might argue that since the measuring occurs by applying pressure to the arterial system it would be considered a maaseh and would therefore be prohibited.

While Rabbis Wosner and Bleich disagree with most contemporary authorities regarding the use of sensors they would agree that Eye Tracking Technology^[4] would be considered a maaseh on Shabbat. Locked-in Syndrome^[5] or pseudocoma is a condition where patients maintain consciousness but are incapable of movement or speech. Importantly the supranuclear ocular motor pathways are spared and patients can therefore move their eyes vertically. Taking advantage of these unique features, scientists used Eye Tracking Technology that is sensitive to patient’s subtle eye movements to allow these patient’s to communicate. Newer technologies from researchers at UCSD^[6] allow for even greater functionality and more possibilities for otherwise immobilized patients. Since eye movement is a purposeful action Rabbis Wosner and Bleich would agree that it would be prohibited to use Eye Tracking Technology on Shabbat for a non-choleh (importantly, the patient in a pseudocoma would still be allowed to utilize the technology). Would the device allow for the pseudocoma patient to shake a lulav, it follows that they would fulfill their obligation^[7].

There are also a number of medical devices that respond to changes in bodily function and require analysis as to their use on Shabbat. Sleep apnea^[8] can be a serious condition where breathing repeatedly starts and stops throughout the night. As the patient’s breathing ceases during the night, they abruptly awaken (usually for too short a period to remember the next morning) resulting in unrestful sleep. Classically, sleep apnea presents in a patient that is consistently tired even after sleeping an adequate number of hours throughout the night. The three most common forms of sleep apnea are: obstructive sleep apnea which occurs due to pathologic muscular relaxation in the throat; central sleep apnea resulting from lack of proper brain signaling to stimulate muscular respiration; and complex sleep apnea syndrome which is a combination of the two. Complications of sleep apnea include daytime fatigue, hypertension, arrythmias, sudden cardiac death, stroke, type two diabetes, metabolic syndrome, nonalcoholic fatty liver disease among others. It is therefore imperative to diagnose and properly treat sleep apnea.

The most specific and sensitive way to diagnose sleep apnea is with nocturnal polysomnography, (type 1 sleep monitoring device) where a patient is hospitalized overnight and their vitals, brain activity, breathing patterns, arm and leg movement and blood oxygen levels are monitored. For patient convenience, home sleep tests, known as type 3 and 4 sleep monitoring device, are also available that measure only some of the parameters on type 1 sleep monitoring devices.

Diagnosis of sleep apnea is rarely urgent, and it is hard to imagine a scenario where it would be a matter of life or death to run a sleep study on Shabbat, much less find a clinic that would be open on weekends to provide the test. Nevertheless, it is of curiosity to determine whether such a test would be allowed to be performed on Shabbat. The analogous medical test, that has previously been discussed, is the ECG where cardiac function is measured and recorded on a piece of paper. It is hard to qualify the cardiac stimulus, an involuntary action, that causes the recording to occur as even an ones. Were one to prohibit running an ECG on Shabbat they would need to argue that placing the probes on the patient is the forbidden act. The same should then be said for diagnosing sleep apnea on Shabbat. The presence of the device is not forbidden as breathing, limb movement etc. are all involuntary acts that occur during sleep; only the placing of the device on the person might be considered a maaseh prohibited on Shabbat.

Treatment of sleep apnea provides an interesting analysis as there are a few types of devices^[9] that lend to various conclusions. As noted, chronic sleep apnea can result in life threatening conditions and therefore treatment, irrespective of the melachot involved would be allowed on Shabbat. However, positive airway pressure therapy, the mainstream types of treatment after failure of lifestyle changes to relieve symptoms, does not necessarily need to be performed every night. It then needs to be determined if there is a halachic reason to avoid administrating therapy on Shabbat.

The first type of positive airway pressure therapy that is usually attempted is continuous positive airway pressure (CPAP). CPAP provides a constant increased pressure to ensure the upper airway passages remain open, preventing the occurrence of apneic episodes. Bilevel positive airway pressure (BPAP) delivers preset inspiratory and expiratory positive airway pressure, assisting the respiratory cycle by increasing pressure on inspiration and decreasing during exhalation. Auto titrating positive airway pressure (APAP) changes the level of airway pressure in response to airflow, change in circuit pressure or snoring. Adaptive servo-ventilation (ASV) constantly responds to the patient’s breathing patterns to ensure the patient remains within 90% of their normal needs.

CPAP on Shabbat should be allowed according to all authorities, assuming the device is turned on in a permissible way, as there is no intervention on the part of the patient that changes the device’s settings. The latter three devices delineated all respond to changes in the patient’s respiratory patterns. Arguably, the authorities mentioned above respond identically to this question. Rabbis Wosner and Bleich imply they would allow the use of the devices on Shabbat, while other authorities would deny their use. However, it is possible that all authorities would maintain the use of ASV’s is allowed on Shabbat. While the other adaptive devices change their setting during both expiration and inspiration, ASV responds only when the patient suffers an apneic episode such that when the patient stops breathing the ASV increases pressure to ensure continued respiration. It is then the lack of a maaseh (not breathing) that results in the response of the device. If so, all authorities should maintain that its use is permissible on Shabbat.

The above sources all discussed how we analyze sensors that respond to some sort of human interaction. In contradistinction is the discussion of how to analyze devices that function by direct neural stimulation. Patients that lose function of one of their limbs have for thousands of years utilized some form of prosthetic. While prosthetics allowed the patients to maintain some form of normalcy, they did not replace biological hands as they could not replace the sophistication of movements of the digits. Their movement was limited by the limb they were attached to and they did not have the capabilities of independent movement as healthy patients can move their fingers or hand without moving the rest of their arms. Moreover, prosthetics did not have sensory capabilities. Robotic limbs are physically attached to the upper limbs but their movement is controlled by wiring directly linked to their respective control center in the brain. Such that, in theory, they can function and feel like a biological hand^[10].

That then leads to the new and virtually undiscussed question, how does halacha consider actions that occur due to direct neurological stimulation. The primary sources discussing these issues are addressed by Rabbi Mordechai Carlebach in his work Chavtzelet Hasharon in regards to the prohibition of preparing the manna served in the desert on Shabbat.

Moshe warns the Jewish people that they must not look for manna on Shabbat because only what, “you bake and cook before Shabbat can be utilized on that day.” At face value, Moshe was informing the people that not only will they receive manna on Shabbat, they should also not prepare other foods on that holy day. However, the Michilta assumes that Moshe was clarifying his statement on the manna, not only would manna not fall on Shabbat, the Jews should also not prepare the manna on Shabbat. That is, the person partaking of the manna decided how they wished their food would taste, and that qualified as preparing food on Shabbat.

The authors of the Tosfos in the Moshev Zikaniem assume that preparing the manna required the partaker to verbally enunciate that which they wished the manna to become. Speaking, then, becomes the action that Moshe informed the Jews was prohibited on Shabbat when it resulted in the preparation of food. However, the Michilta does not assume a verbal request was necessary, one only needed to imagine the taste they wished for the manna and so it tasted.

The Michilta’s presentation lends to a model with which we can analyze the halachic view on robotic limbs. The Michilta, and the Rishonim who follow its position, assume that neurological stimuli that result in the subsequent movement of the robotic limbs would be attributed to the person and considered halachic maaseh. Significantly, mitzvot that require an action (i.e. shaking a lulav) would then be considered fulfilled by the robotic arm. In regards to hilchot Shabbat, Rabbi Weiss, quoted in an essay by Rabbi Sprung^[11], does not go as far as assuming the robotic arm can be considered a complete maaseh, however, he does ascertain that the movement of the arm should at least be a gramma.

Rabbi Weiss’ position is somewhat puzzling. The use of the robotic limb on Shabbat does not transgress one of the thirty-nine melachos. Only the subsequent action taken by the robotic limb can be considered one of the forbidden melachos. That is to say, a robotic arm that turns on the stovetop on Shabbat does not transgress an issur of using the robotic arm and turning on the stovetop; only the latter constitutes an issur melacha. This means neurological stimuli (thinking) resulted in the movement of the robotic arm that then light a fire on Shabbat. The Rishonim’s description of the Michilta assumes that the preparation of food by thought is a problem of tikkun manna, limiting the ability of thought to be considered a maaseh on Shabbat only to tikkun manna. To assume Rabbi Weiss’ position, the argument would need to be that thought which caused movement of the robotic arm that then turned on the stovetop would also be tikkun manna. It is not at all obvious that tikkun manna would still be an issue when the forbidden action is so far removed from the person’s initiation of the action.

As discussed above, Eye Tracking Technology is used to help pseudocoma patients communicate while in a semi-comatose state through eye movement which is considered a halachic maaseh. Recently two newer advancements change the halachic consideration of their communication. Dr. Niels Birbaumer, a neuroscientist at the University of Tubingen, used variations in blood flow to different regions of the brain that were tracked by infrared light to determine which blood flow signified “yes” or “no”. It is possible that even those authorities who assume thinking can be considered some form of maaseh would concede that this system does not meet the halachic threshold of maaseh. Narrowly defined, thought is the result of chemical stimuli conducted by neuronal electrical changes. Birbaumer’s system does not track those changes, it only tracks the blood flow changes that result from the use of different areas of the brain. That then might be allowed according to all authorities to be used on Shabbat. Unfortunately, that would also result in not being able to utilize this system to free a woman of being an aguna as there is no maaseh demonstrating the man’s wishes to divorce his wife.

A more invasive, but more capable, system described in Nature uses brain chips to allow a paralyzed patient to write on a computer screen through the use of Brain-Computer Interface technology. The brain chips track neural activity involved in writing and allow the simple thought of writing to cause writing to be formed on a screen. This seems to be analogous to the use of robotic limbs previously described, however, Rabbi Carlibach demonstrates that there may be a unique difference.

Famously, Moshe died on Shabbat. On the last day of his life, the Torah tells us that Moshe wrote a Sefer Torah for each of the tribes. That then leads to the fascinating discussion analyzing how Moshe wrote on Shabbat. One of the options is that Moshe used Hashavat ha’Kulamis to write the Torah. Assuming that Moshe deployed the device on Shabbat it should integrally not solve the issue. Either Hashavat ha’Kulamis is an action attributed to Moshe in which case the Torah is kosher as there was an act of writing that caused the Torah to be written but it would be prohibited to utilize it on Shabbat or Hashavat ha’Kulamis is a separate action not related to Moshe which would be permitted on Shabbat but would not be considered a maaseh and the Sifrie Torah written by it would not be kosher.

The Pnei Yehushua is bothered as to why is there a separate prohibition of amira l’nachri on Shabbat, the prohibition should be included under the guise of shlichot, at least according to the authorities who maintain that there is a prohibition of shlichot l’chumra. In explanation, the theory is advanced that on Shabbat shlichot would not be prohibited as there is no maaseh being done by the one who recruited the messenger. Therefore, by the very nature of the requirement of maaseh on Shabbat, another prohibition was required to prevent requesting the aid of a nachri. Rabbi Carlibach uses this analysis to assume that there are two types of maaseh. For Shabbat there is a much higher threshold to consider an action a maaseh. However, writing a Sefer Torah has a much lower threshold for what is considered a maaseh. Therefore, utilizing Hashavat haKulamis would simultaneously be a maaseh for writing a Sefer Torah and not a maaseh that is prohibited on Shabbat. Accordingly, Rabbi Carlibach’s analysis would result in the surprising conclusion that writing accomplished by brain chips is permitted on Shabbat and would allow for acknowledging a patient’s wish to divorce his wife.

In summation thus far:

This analysis may miss the fundamental point on how to consider the application of these technological advancements on Shabbat. As opposed to sensory function, where Halacha might consider the neurological processes to be paramount such that a cochlear implant would be considered halachic hearing; halachot that require a maaseh demand muscular intervention irrespective of the neurological process that stimulated it. In biological terms, halachot that require sensory recognition utilize central nervous sensory recognition by an external stimulus. On the other hand, halachic action requires peripheral nervous system stimulation of muscular function. Therefore, robotic arms, blood flow changes, and brain chips would not be considered a maaseh at all by the very nature of the fact that no biological muscular intervention was involved.

Endnotes

1. Most of the relevant sources are quoted by Rabbi Bleich in footnote (5). Here is a list of more recent authorities that discuss similar issues:

   Rabinowitz NE, Use of Sensors on Shabbat with Speech and Thought. Tchumin 36, תשעו.

   Is it Allowed to Wear a Fitbit on Shabbat. Accessed September 3, 2021.

   Rosen Y. Smart Band on Shabbat. Accessed September 3, 2021.

   Sultan I, Wearing a Smartwatch on Shabbat.  Accessed September 3, 2021. ↑

2. For a full halachic analysis see Bleich JD, Survey of Recent Halakchic Periodical Literature: Use of Surveillance Systems on Shabbat, section III. Tradition, Fall 2001. 35.3. The arguments presented in this paper are the implications of Rabbi Bleich’s position and not what he actually wrote. ↑

3. Iggeret Moshe OCH Volume I number 128. See also, Chelkat Yaakov vol 3 number 24, Meiri Eish chapter 2 p. 66, Mahari Shteif number 123, Minchat Yitzchak vol 3 number 142, Teitz Eliezer vol 11 numbers 37 and 38, Shevet haLevi vol 1 n. 61. ↑

4. Environmental Control System for Locked-in Syndrome Patients Using Eye Tracker  ↑

5. Locked In Syndrome ↑

6. https://eyegaze.com/ ↑

7. For a full analysis of whether shaking the lulav requires the use of the upper limbs or if any part of the body causes the lulav to shake see Cohen YA Stem Cell Therapy in Halacha Assia. ↑

8. Clinical presentation and diagnosis of obstructive sleep apnea in adults  ↑

9. Obstructive sleep apnea: Overview of management in adults  ↑

10. https://www.science.org/doi/10.1126/scirobotics.abf3368 ↑

11. Sprung Y Is an ALS Patient Allowed to Use Medical Devices on Shabbat. . Accessed September 3, 2021. Sprung Y, Are You Allowed to Do a Prohibited Action on Shabbat through Thought. . Accessed September 3, 2021. ↑