Rabbi Itamar Rosensweig and Rabbi Alex Maged
When one party acts negligently, and harms another party as a result, the negligent party must compensate the victim for their damages. Suppose, however, that the victim also acted negligently, and that their own negligence was partly responsible for the harm they sustained. Should the negligent victim retain a right to compensation in such circumstances? If so, should the negligent victim receive full compensation, or should their damages award be reduced to reflect the partial responsibility that they bear for their own harm?
In our previous article, we examined sources that establish a halakhic principle of contributory negligence, under which a tort victim’s recovery might be totally barred when they bear responsibility for the harm they sustained. In this article, we will now examine sources that support a halakhic principle of comparative negligence, per which a tort victim’s recovery might be partially reduced, though not completely precluded, when they contribute to their own injuries.
The two fundamental principles that would yield a halakhic doctrine of comparative negligence are well-established in Jewish law. The first principle is that a victim’s right to recover tort damages may be negatively impacted when their own negligence contributed to their damages. This is the principle we discussed in our previous article, and as we documented there, it has broad support among halakhic authorities. The second principle is that tortfeasors are only liable for the share of damages that they cause, but are exempt for any share of damage sustained by the victim due to some other source. This, too, is a strongly supported halakhic principle. Taken together, these two principles yield a halakhic doctrine of comparative negligence: a tortfeasor should not be liable for the share of damages caused by the victim, and the victim’s right to recover should be reduced in proportion to the amount they contributed to their own harm. That said, no Talmudic case explicitly combines these two principles to articulate a clear rule of comparative negligence.
Our goal in this article, then, is to explore the halakhic validity of a comparative negligence rule. We do so in two ways. First, we will consider whether it is possible to derive a comparative negligence rule from existing case law. To do so, we will find categories of tortfeasors who pay less than full damages under established halakha, and will evaluate whether the comparatively negligent tortfeasor can be reasonably characterized so as to fit into one of these established categories, such that the legal outcome applicable in those cases would apply in our case as well. Second, we will consider whether it is possible to locate a comparative negligence rule within existing case law. To do so, we will find, here again, categories of tortfeasors who pay less than full damages under established halakha, but this time, we will try to show that the halakhic ruling in those cases actually presupposes a rule of comparative negligence. Put another way, under the first approach, we will be grounding the halakhic rule of comparative negligence in other, pre-existing halakhic tort principles, whereas under the second approach, we will argue that in fact, those pre-existing tort principles are themselves grounded in the more fundamental principle of comparative negligence—even if that underlying principle is not explicitly identified as such.
Applying these approaches, we will consider, in this article, two particular categories of tortfeasors who pay less than full damages under established halakha: joint tortfeasors (שותפים בנזק), which might provide a model for a comparative negligence rule; and reciprocal tortfeasors (חבלו זה בזה), which might either provide a model for comparative negligence, or which might in fact presuppose such a principle. Under the paradigm of joint tortfeasors (שותף בנזק), the negligent victim will be characterized as having harmed themselves, while under the paradigm of reciprocal tortfeasors (חבלו זה בזה), the negligent victim will be characterized as having harmed the tortfeasor. That said, characterizing the negligent victim in these ways, for the purposes of a comparative negligence rule (i.e. merely reducing their recovery), poses some doctrinal complications that are perhaps not as challenging in the context of contributory negligence (i.e. completely barring their recovery). We will note some of those complications in our discussion as well.
A. Theory #1: Negligent Victim as Joint Tortfeasor (שותף בנזק)
- The Theory
Our first halakhic theory of comparative negligence appeals to the law of joint tortfeasors. Under the law of joint tortfeasors, two tortfeasors who mutually harm a victim must compensate that victim in proportion to the harm that each one caused. Thus, for instance, if the first tortfeasor is 40% liable for the victim’s injuries, and the second tortfeasor is 60% liable, then the tortfeasors would be individually liable for 40% and 60% of the victim’s damages, respectively. As applied to our case, this theory would characterize the comparatively negligent tort victim as a joint tortfeasor together with the actual tortfeasor. Put another way, the victim who contributes to his own harm would be viewed, under this theory, as having acted in concert with the actual tortfeasor to injure himself. Practically, then, if the victim’s negligence was, say, 40% responsible for his injury, then he could recover that portion of the damages only from “himself.” All he could recover from the actual tortfeasor would be the remaining 60%.
The key idea here is that every instance of comparative negligence can be characterized as a case of joint tortfeasors, which yields identical legal outcomes to an actual doctrine of comparative negligence.
- The Authority
The legal principle of joint tortfeasors, which underlies our first theory, is firmly established in Jewish law. For example, the Talmud discusses a case involving six people who sit on a bench. If the bench breaks as a result of their combined force, each person is liable to pay for his share of the damage. Based on this case and similar cases in the Talmud, Rambam and Shulchan Arukh codify the general principle that tortfeasors who participate jointly in inflicting damage upon a tort victim split the damages between them, with each party bearing their share of the liability. Several other authorities explicitly endorse the principle that liability should be apportioned among joint tortfeasors according to each party’s contribution to the harm.
- The Challenge
The challenge with our first theory is that it appears to present a single party as both tort victim and the tortfeasor in the same cause of action. It does this by characterizing the negligent victim as a joint tortfeasor vis-à-vis the damage he suffered. Yet the principle of joint tortfeasors typically applies to defendants. It is not obvious that this principle can be applied to the plaintiff himself in his own cause of action.
Nevertheless, the crucial step of characterizing a negligent victim as a joint tortfeasor in his own harm has already been taken by Or Sameach. Or Sameach posits the following case. Suppose that Reuven dug a pit but failed to guard it appropriately. Suppose further that Shimon owns two oxen, and that one of Shimon’s oxen pushes the other one of Shimon’s oxen into Reuven’s pit. Or Sameach argues that Shimon (the ox owner) is a joint tortfeasor together with Reuven (the pit owner) in damaging his own ox. As such, Or Sameach concludes, Shimon should recover only those damages arising from Reuven’s share of the negligence, but not the damages arising from his own share. This is an explicit application of the comparative negligence principle, modelled upon the law of joint tortfeasors. Thus, there is precedent to support the theory that a tort victim can be characterized in the same cause of action as both a victim and joint tortfeasor in his own harm. 
More fundamentally, we may not need to characterize the negligent victim as actually occupying the role of tortfeasor against himself in order to preserve our basic analogy between that victim and a joint tortfeasor. For our purposes, it is sufficient to treat the negligent victim as a joint tortfeasor merely in the sense that no other parties are liable for that share of harm which he brought upon himself. Put otherwise, the rule of joint tortfeasor liability can be conceptualized in two different ways. Phrased positively, the rule provides that a joint tortfeasor is liable for whatever share of harm he personally causes. Phrased negatively, however, the rule provides merely that a joint tortfeasor is not liable for any share of harm that he did not personally cause. If this second, weaker formulation of the principle is applied to a tortfeasor whose victim was comparatively negligent, that principle alone would suffice to exempt the tortfeasor from the share of harm caused by the victim. This weaker application of the principle does not depend upon characterizing the victim’s share of negligence in any sense. It depends merely on recognizing that the tortfeasor was not the source of that particular share of negligence.
B. Theory #2: Negligent Victim as Reciprocal Tortfeasor (חבלו זה בזה)
- The Theory
Our second halakhic theory of comparative negligence is modelled upon a law pertaining to reciprocal tortfeasors. Under the law that we will consider, where two tortfeasors harm each other, their damages offset, and the party who sustained greater damage receives the difference from the other party. As applied to our case, this theory would characterize the comparatively negligent tort victim as a reciprocal tortfeasor of the actual tortfeasor. Put another way, the victim whose negligence contributes to his own harm would be viewed, under this theory, as having harmed not only himself through his negligence, but also his tortfeasor. One possible justification for this characterization, which we encountered in our previous article, is that a tort victim whose own negligence amplifies his losses thereby increases the amount in damages that his tortfeasor must pay him as compensation. By imposing this additional cost upon the tortfeasor—beyond what the tortfeasor ought to have paid on account of his own conduct—the victim “harms” that tortfeasor financially, and it is this harm, we might argue, which the actual tortfeasor recovers when he deducts that value from the full damages owed to the victim. Practically, then, if the victim’s negligence was, say, 40% responsible for his injury, then he would “owe” that portion of his injury to the tortfeasor, as compensation for causing the tortfeasor to incur the increased portion of liability. The tortfeasor would therefore deduct that amount from the full damages owed to the victim, leaving him with a net obligation of 60%.
To be sure, it is no simple matter to characterize the marginal increase in damages that the tortfeasor owes to the victim on account of the victim’s negligence as a “harm” imposed by the victim upon the tortfeasor. We will address that issue below. Notice, though, that this theory avoids the problem inherent in the previous theory: here, unlike there, the victim is not conceived of as both the plaintiff and the defendant in the same cause of action. Instead, the case is conceived as involving two separate causes of action: a first cause of action in which the victim sues the tortfeasor, and a second cause of action in which the tortfeasor countersues the victim.
- The Authority
The legal principle underlying our second theory derives from a series of Mishnahic cases involving two oxen—or two people, or one person and an ox—each of whom harms the other and is harmed by that party in return. Although it will be necessary to examine the most complex of these cases later on, for now it will suffice to consider a simplified version of the most basic case. Suppose that Reuven and Shimon both own oxen and that both owners fail to guard their oxen appropriately. Suppose that as a result of this failure, Reuven’s ox gores Shimon’s ox, inflicting $100 worth of damage, and that Shimon’s ox likewise gores Reuven’s ox, inflicting $50 worth of damage. Suppose further than no other tort principles apply that would spare either Reuven or Shimon from paying full damages when their oxen gore. In this scenario, the Mishnah rules that the damages are netted against each other, leaving Reuven liable to pay Shimon $50 ($100—$50).
When we consider the above scenario from Shimon’s perspective, we discover that the amount which he can recover, as the victim of Reuven’s tort, is directly reduced by the value assigned to his own tortious act. That is, Reuven’s tortious conduct cost Shimon $100 of damage, but Shimon’s tortious conduct cost Reuven $50 of damage. Thus, we deduct the value of Shimon’s tort from the value of Reuven’s tort in order to determine how much Shimon can ultimately recover.
Now return to the case of the comparatively negligent victim. In this case, too, the victim acts tortiously; and in this case, too, the victim’s tortious conduct imposes costs upon the tortfeasor—here, in the form of increased tort liability that the tortfeasor would not otherwise have incurred. If, then, we were to characterize the victim’s act of imposing such additional costs upon the tortfeasor as a form of cognizable harm (נזק) committed against that tortfeasor, then perhaps we could reduce the tortfeasor’s liability in such cases by applying the same principle which would require the greater of two joint tortfeasors to pay the lesser tortfeasor only the net damage produced between them. This would effectively result in a halakhic rule of comparative negligence.
The key idea here is that the cases of comparative negligence can be characterized as cases of reciprocal tortfeasors. Applying the principle of reciprocal tortfeasors would yield results identical to a comparative negligence rule.
- The Challenge
The challenge with our second theory is that it characterizes an indirect harm, i.e., amplifying the tortfeasor’s liability, as a cognizable harm under halakha. The theory does this by assigning liability to the tort victim for the economic costs indirectly imposed upon the tortfeasor as a result of the victim’s negligence. Yet as a general principle, only certain forms of indirect harm (“garmi” harms) are cognizable under halakha, whereas many other forms are not (“gerama” harms).
However, the distinction between cognizable and non-cognizable forms of indirect harms is subject to dispute among the commentators. Thus, our case may conceivably fall outside the scope of the gerama exemption.
Alternatively, and more fundamentally, the gerama exemption might be completely irrelevant for our case. For while the gerama rule does treat indirectly caused harms as legally insignificant, it does so only for a very specific purpose. Under the gerama rule, indirectly caused harms are not legally significant enough that we would compel a tortfeasor who caused such harms to pay compensation for having caused them. However, indirectly caused harms may be significant enough to offset the claims of a victim-plaintiff who imposed such harms on a tortfeasor-defendant in the same legal action. After all, when we characterize the comparatively negligent victim-plaintiff as a reciprocal tortfeasor by virtue of his amplifying the liability of the tortfeasor-defendant, the legal question is not whether the victim-plaintiff must pay out damages, but whether the victim-plaintiff’s role in causing the tortfeasor-defendant to incur additional liability is sufficient to offset and exempt the tortfeasor-defendant from those (additional) damages. Thus, even if the causal role of the victim-plaintiff in magnifying the liability of the tortfeasor-defendant formally amounts to gerama, it is gerama that works to extinguish the liability of the tortfeasor-defendant. The outcome of our case is thus fully consistent with the rules of gerama.
C. Theory #3: Reciprocal Tortfeasor as Negligent Victim (חבלו זה בזה)
- The Theory
Our third halakhic theory of comparative negligence is a variation of the second in that it, too, looks to the law of reciprocal tortfeasors. Unlike in the previous section, however, where we used the principle of reciprocal tortfeasors as a model that would generate legal outcomes identical to a comparative negligence rule, here we will consider whether the relationship might be reversed—that is, whether a principle of comparative negligence may actually underly the law of reciprocal tortfeasors. To see how this might be, we will return once again to the case of the reciprocal tortfeasors, and this time, consider one of its variants in greater detail.
- The Authority
The Legal Rule
As described in the previous section, the halakhic treatment of reciprocal tortfeasors derives from a series of Mishnahic cases involving two parties, each of whom harms the other and is harmed by that person in return. Above we considered the simplest version of these cases. Here, however, let us consider a more complex case. The case involves two ox owners: one whose ox is a tam (literally: “innocent”) and another whose ox is a mu’ad (literally: “forewarned”). A tam ox is one who has no established history of goring, and whose owner generally pays only half damages when it gores. A mu’ad ox is one who does have an established history of goring, and whose owner generally pays full damages when it gores. The case addresses how damages are apportioned when the owner of a tam ox and the owner of a mu’ad ox each negligently fail to guard over their oxen, leading those oxen to gore one another. If the mu’ad ox causes greater damage than the tam ox, then, per the Mishnah, the owner of the mu’ad ox must pay “מותר נזק שלם”—“net of the full damage.”
Commentators debate how precisely this rule is to be applied. Let us illustrate the debate through an example. Suppose Reuven’s ox is a mu’ad and Shimon’s ox is a tam. Suppose further that Reuven’s mu’ad ox inflicts $100 of damage upon Shimon’s tam ox, and that Shimon’s tam ox inflicts $40 of damage on Reuven’s mu’ad ox. How do we determine how much money Reuven owes Shimon in this case?
According to Rambam, we apportion damages in the case of the goring oxen by netting the legal liabilities (מותר חיוב). This means, in effect, that we analyze each act of goring separately, and allocate liability for each act per the usual rules applicable to goring oxen. Applying this approach, Reuven’s legal liability is $100 ($100 of damage inflicted x 100% recovery because Reuven’s ox is a mu’ad) and Shimon’s legal liability is $20 ($40 of damage inflicted x 50% recovery because Shimon’s ox is a tam). Thus, the net liability is $80 ($100 of Reuven’s liability — $20 of Shimon’s liability), and Reuven owes Shimon this sum.
According to Rosh, however, we apportion damages by netting the actual injuries (מותר חבלה). This means, in effect, that we ignore the usual rules applicable to goring oxen and instead simply consider the economic impact of each ox’s respective damage. Here, Reuven’s ox inflicted $100 of damage, and Shimon’s ox inflicted $40 of damage. Thus, Reuven’s ox inflicted $60 of net damage upon Shimon’s ox ($100 of Reuven’s damage to Shimon — $40 of Shimon’s damage to Reuven). Since Reuven’s ox is a mu’ad, Reuven owes Shimon the full $60 ($60 net damage inflicted x 100% recovery because Reuven’s ox is a mu’ad).
The Implication of the Legal Rule
The debate between Rambam and Rosh regarding how we apply our Mishnah’s rule for apportioning damages may implicate whether or not we can locate a principle of comparative negligence within our case. Both Rambam and Rosh agree that Reuven owes Shimon for negligently harming him. Both agree, moreover, that Reuven’s obligation to Shimon is reduced because Shimon also acted negligently. Where the commentators diverge, however, is on how precisely Shimon’s act of negligence affects his recovery.
According to Rambam, Shimon’s act of negligence has no special effect upon his right to tort recovery. That is because, for Rambam, we treat each act of goring as an independent act of negligence: in order to determine each tortfeasor’s individual liability, we apply to each tortious act the standard rule of tort liability pertinent to its particular negligence category (i.e. tam-negligence vs. muad-negligence). Only afterwards do we net the monetary damages produced by this analysis. Thus—and this is the key—the netting process is in no way affected by the tortious nature of the liabilities in question.
According to Rosh, by contrast, Shimon’s act of negligence does have a special effect upon his right to tort recovery. That is because, for Rosh, we do not treat each act of goring as an independent act of negligence. Instead, the fact that the victim also contributed harm changes the way we conceptualize the tort overall: rather than analyzing each act individually, and applying to each tortious act the standard rule of tort liability pertinent to its particular negligence category (i.e. tam-negligence vs. muad-negligence), we evaluate the parties’ actions in toto. Put another way, Rosh conceptualizes the case of reciprocal harm as consisting of a single tortious act, defined by the net harm. That is, instead of viewing Reuven as having inflicted $100 of damage on Shimon, and Shimon as having inflicted $40 on Reuven, Rosh characterizes the event as a single tortious act defined by the $60 of damage (the net amount, $100 – $40) that Reuven imposed on Shimon (“אין כאן חבלה אלא המותר”).
On Rosh’s interpretation, the Mishnah’s ruling appears to presuppose a principle akin to comparative negligence. For Rosh defines the tort in the Mishnah’s case exclusively in terms of the harm that Reuven imposed upon Shimon; in his view, as mentioned, the case involves a single tortious act defined by the net damage (אין כאן חבלה אלא המותר). Yet whereas Reuven inflicted $100 worth of material damage upon Shimon, Shimon only recovers $60. Why is Shimon barred from recovering the remaining $40 of damage he suffered? The answer appears to be that Shimon is barred from recovering $40 because that is the amount Shimon (the victim) contributed to (Reuven’s) tort through his own negligence. Thus, Rosh’s analysis presupposes the legal doctrine that a tortfeasor is not responsible for the portion of harm contributed by the victim—i.e., the doctrine of comparative negligence. Put another way, Rosh’s reading of our Mishnah represents at least one instance within established halakhic case law wherein the principle of comparative negligence is implicitly operative.
Where a tort victim bears some responsibility for their injuries, halakha offers several possible approaches for barring or reducing their recovery.
The grounds for barring recovery completely are more firmly established. As we discussed in our previous article, such an outcome might result on the theory that the tort victim is at fault for harming themselves (איתזיק בנפשיה); that they are at fault for imposing additional liability upon the tortfeasor (השבת אבדה); that they absolved the tortfeasor from fault through implicitly consenting to the possibility of injury (מחילה); or that, as a result of the tort victim’s negligence, the tortfeasor’s conduct now lacks the degree of causal connection to the victim’s injuries that must be established in order to hold the tortfeasor liable for those injuries (מעשיו גרמו לו).
The grounds for merely reducing recovery in proportion to the victim’s share of responsibility are less firmly established. As we discussed in this article, such an outcome might result on the theory that the tort victim can be characterized as a joint tortfeasor (שותף בנזק) in causing their own injuries, or that the tort victim can be characterized as having reciprocally harmed (חבלו זה בזה) the actual tortfeasor by negligently increasing the scope of the tortfeasor’s liability. However, these theories raise unique doctrinal challenges that may perhaps warrant further inquiry. Alternatively, these challenges may be irrelevant if, instead of grounding a comparative negligence principle in other tort principles, it turns out that one of those principles is actually itself grounded in a principle of comparative negligence. In that case, the principle of comparative negligence already functions within the halakhic system—a possibility we examined in the context of Rosh’s interpretation of reciprocal tortfeasors (חבלו זה בזה).
 Rabbi Itamar Rosensweig is a dayan and chaver beth din at the Beth Din of America and a maggid shiur at Yeshiva University. Rabbi Alex Maged received his J.D. from Harvard Law School and formerly served as a legal intern at the Beth Din of America. This article was originally prepared in January 2021 and is being published now in conjunction with the forthcoming edition of the Journal of the Beth Din of America.
 See Itamar Rosensweig and Alex Maged, “Contributory Negligence in Jewish Law,” Jewishprudence, April 2021.
 Historically, several factors prevented common law courts from embracing the doctrine of comparative negligence. These included “the notion of the indivisibility of any single injury” and “the lack of any definite basis for apportionment.” Page Keeton and William Lloyd Prosser, Prosser and Keeton on Torts (1984), p. 470. Cf. Helf v. Glanding (“[T]he law cannot measure how much the damage suffered is attributable to the plaintiff’s own fault. If he were allowed to recover, it might be that he would obtain from the other party compensation for his own misconduct.”) However, “there has been for many years an increasing dissatisfaction with the absolute defense of contributory negligence.” Prosser op. cit., p. 469. The reason for this shift is that the doctrine of contributory negligence “places upon one party the entire burden of a loss for which two are, by hypothesis, responsible. The negligence of the defendant has played no less a part in causing the damage.” Id. See also Haeg v. Sprague, Warner & Co. Inc., 202 Minn. 425, 429, 281 N.W. 261, 263 (1938) (“the rule of comparative negligence would serve justice more faithfully than that of contributory negligence”).
 See, e.g., Shulchan Arukh Choshen Mishpat 410:13. See also infra n. 10.
 In general, Talmudic case law tends to focus more on determining liability than on apportioning damages once liability has been determined. Even where the Talmud finds a tortfeasor liable, it is as open question how damages are to be apportioned between the parties. See, e.g., Rambam, Hilkhot Sekhirut 3:6; Raabad, ad. loc.
 Tosefta Bava Kamma 2:9; Bava Kamma 10b.
 For some examples of joint tortfeasors in the Talmud, see Bava Kamma 10b and Choshen Mishpat 383:3; Bava Kamma 19b and Choshen Mishpat 390:10; Bava Kamma 21b and Choshen Mishpat 392:1; Bava Kamma 53a-b and Choshen Mishpat 410:32-34. For an overview of cases of joint tortfeasors in the Talmud, see Pitchei Choshen, Nezikin 10:25-33.
 See Bava Kamma 10b; Rambam, Hilkhot Chovel U-Mazik 6:13-17.
 Shulchan Arukh Choshen Mishpat 383:3.
 See, e.g., Tur Choshen Mishpat 410 (“דוקא עד שיעור מה דהוה חייב ביה אהאי נזקא היכא דהוה עביד ליה איהו לחודיה אבל טפי לא.”); Sema Choshen Mishpat 410:57 (first interpretation); Ketzot Ha-Choshen 410:3. See also Shulchan Arukh Choshen Mishpat 410:13 (“חפר אחד שמונה ובא חבירו וחפר עוד טפח, שניהם חייבים בנזקין, כל אחד לפי מה שחפר”.); Pitchei Choshen, Nezikin 10:31 n. 67 (“”היה הספסל עומד להשבר מחמת הראשון תוך ב’ שעות, ומחמת ישיבת השני נשבר קודם לכן, שניהם חייבים… נראה פשוט שאם הראשון גרם שנתרועע הספסל בישיבתו… חייב מה שנפחת הספסל מחמתו… שיש לשער כמה שוה חפץ שיכול לעמוד ב’ שעות וכמה שוה שיכול לעמוד שעה אחת וההפרש ישלם השני לבד”. ). Other authorities write as though joint tortfeasors split the liability evenly. But it is possible that this is only true when either: (a) each party’s contribution was sufficient to cause the damage on its own, i.e., each party was a sufficient cause of the harm; or (b) there is no possibility of a fruitful inquiry to determine each party’s actual contribution. In such cases, an even split between the joint tortfeasors is quite reasonable. For an example of the first type of case, see Bava Kamma 53a ((“האי כוליה היזקא עביד והאי כוליה היזקא עביד”. For an example of the second type of case, see Shulchan Arukh Choshen Mishpat 383:4 (“אם אין ידוע כולם משלמים בשוה”).
 In theory, one could raise a similar challenge against the first theory of contributory negligence discussed in our previous article. Contributory Negligence in Jewish Law, op. cit. After all, that theory similarly characterizes the negligent victim as having acted negligently against themselves. That said, the challenge is stronger against our current, comparative negligence theory, because this theory requires us to formally analogize the negligent victim to a joint tortfeasor, in order to import to our case the precedent of partial tort recovery. Taken to its logical extreme, this analogy might imply that the negligent victim technically functions as both a plaintiff and a defendant in the same cause of action.
 Or Sameach, Nizkei Mammon 12:19. Moreover, there are many cases in the Talmud and halakhic literature where the negligent plaintiff is characterized as having “harmed himself” (“איהו איזיק אנפשיה”). For several examples, see our previous article, Contributory Negligence in Jewish Law, op. cit.
 Or Sameach, Nizkei Mammon 12:19. (“כיון דאיהו גרים לנפשיה, היינו ששורו דחף שורו… איהו שותף בנזק כמו… בעל הבור… דהוא [ר”ל בעל השור] עשה היזק כמו בעל הבור… וע”ז אין צריך לשלם בעל הבור, כיון שבעל השור הזיק שור של עצמו…”). See also Pitchei Choshen, Nezikin 10:27 n. 55, discussing Or Sameach’s case (“פשוט שאין בעל הבור משלם אלא חצי הנזק, כיון שהשור שלו [של הניזק] הוא הדוחף, והרי זה כאילו הוא עצמו [ר”ל הניזק] שותף לנזק.”).
 Mishnah Bava Kamma 8:6 may shed light on this question. The Mishnah rules that one who inflicts an injury upon himself (“חובל בעצמו”) is “exempt” (“פטור”) from damages. This might imply that in principle self-harm does trigger a cause of action—after all, one cannot be “exempted” from a claim that was incognizable to begin with. If so, then an individual could theoretically occupy the role of both victim and tortfeasor in the same course of action. To be sure, one might be tempted to read “exempt” as referring to a different cause of action: the prohibition against destroying God’s creatures (“בל תשחית”). But that reading is inconsistent with the fact that, in the very same breath, the Mishnah compares the exemption for self-injury with a ruling of financial liability for others who impose harm on him (“אחרים שחבלו בו חייבין”). This comparison implies that “exempt” and “liable” in this clause of the Mishnah refer to the same type of tort liability (i.e., compensation). See Tosafot, Bava Kamma 91b, s.v. ha-chovel; Tiferet Yisrael, Bava Kamma 9:6, 39.
 This theory of comparative negligence bears strong similarities to Chiddushei Ha-Rim’s approach to contributory negligence, which we discussed in our previous article. Chiddushei Ha-Rim, Hilkhot Dayyanim 25, s.v. amnam. Chiddushei Ha-Rim argues that a victim wrongs the tortfeasor when he negligently fails to avoid the harm that the tortfeasor set in place—for example, by failing to remove the burning coal that the tortfeasor placed on his garment. Such failure breaches the victim’s duty to “rescue” the tortfeasor from incurring liability (“השבת אבדה”). As such, the victim forfeits his right to recover damages. See Contributory Negligence in Jewish Law, op. cit., n. 27-30. Like Chiddushei Ha-Rim, we also characterize a negligence victim as wronging the tortfeasor under the present theory of comparative negligence. However, for Chiddushei Ha-Rim, the wrong is one of nonfeasance: the victim failed to rescue the tortfeasor from liability. For us, it is one of malfeasance: the victim caused the tortfeasor to incur (additional) liability.
 Bava Kamma 33a.
 Note that the challenge discussed here may not apply with equal force to the parallel theory of contributory negligence discussed previously. Here, like there, the marginal harm produced by the victim’s own negligence is viewed as producing some derivative harm to the tortfeasor. But here, that marginal harm is formally characterized as a tort injury (“נזק”), whereas there, Chiddushei Ha-Rim characterized the marginal harm as a “lost object” which the victim was required to “return” to the tortfeasor (“השבת אבדה”). On the other hand, Chiddushei Ha-Rim’s characterization raises challenges of its own. Most fundamentally, it is not at all clear that the duty of returning lost objects can be applied to “returning” hypothetical future economic “liabilities,” such as the liability that the tortfeasor would incur if a plaintiff were permitted to court additional injury at the tortfeasors’ expense.
 Per one view, the harm is sufficiently direct so long as it results from the actions of the tortfeasor himself. Per another view, it is sufficiently direct so long as there is no meaningful time delay between the tortious conduct and the injury. Per yet another view, the harm is sufficiently direct so long as it is the sort of harm that occurs with reasonable frequency. See Tosafot, Bava Batra 22b, s.v. “zot.” For an overview of gerama and garmi, see Encyclopedia Talmudit Vol. 6, s.v. gerama and garmi. Whether the harm caused by the comparatively negligent tort victim qualifies as a halachically cognizable harm would thus depend on how it is characterized under these directness criteria.
 The distinction between compelling a tortfeasor to pay, on the one hand, and offsetting liability, on the other, would also defeat a similar challenge one could raise against our theory based on the halakhic principle that blocks tort recovery for “indiscernible damage” (“היזק שאינו ניכר”). See generally Encyclopedia Talmudit Vol 9, s.v. hezek she-eino nikkar. It is not clear whether the reciprocal harm imposed by the negligent victim upon the tortfeasor by amplifying his liability would constitute a form of indiscernible damage.
 Bava Kamma 33a.
 Rambam, Hilkhot Nizkei Mammon, 9:14.
 Rosh, Bava Kamma 3:13.
 To that extent, Rambam’s rule is not fundamentally a tort rule. It is a generic debt rule. We could apply the same netting process to any other type of offsetting debt (for example, reciprocal loans) without any need to adjust the way the rule operates.
 Rosh’s novel characterization of our case as involving only one tortious act bears halakhic implications beyond the issue of comparative negligence. See, e.g., Reshimot Shiurim Bava Kamma, s.v. Tosafot d”h shnei.
 The answer cannot be that Reuven’s $100 obligation to Shimon is offset by Shimon’s $40 obligation to Reuven. That way of thinking is consistent with Rambam’s view that two tortious events occurred in this case, but it is inconsistent with Rosh’s view that a single tortious event occurred. Indeed, had Rosh treated these as two separate torts, then only $20 should be offset, since Shimon’s ox, as a tam, is liable only for half damages. Yet Rosh requires Reuven to pay $60. This result is reached only because Rosh views the case as involving a single tortious act that Reuven committed against Shimon.
 It is worth considering another Talmudic principle which may presuppose the doctrine of comparative negligence. As we saw above, when a tam (i.e., “innocent”) ox gores, its owner is liable to pay half-damages. See Bava Kamma 15a. Why is the owner’s liability reduced by one-half? Some contemporary tort scholars interpret Rambam in Moreh Nevukhim 3:40 as explaining the half damages rule as a comparative negligence rule. They write:
From the context of what Maimonides writes… it would appear that… since it is not the way of the ox to gore frequently, his owner does not know what caused the ox to gore that particular time and how to prevent such infrequent behavior in the future. In this case it is preferable to split the liability between the owner of the ox and the victim, for the injured party, too, ought to have taken precautionary measures on his part and been wary of the ox even if it was not considered a mu’ad ox, since all oxen can potentially gore. Yuval Sinai and Benjamin Shmueli, Maimonides and Contemporary Tort Theory (2020), p. 236
On their interpretation of Rambam, the owner’s liability is reduced by a half because the victim is deemed to have been 50% comparatively negligent for not having taken proper precautions. Note, however, that the comparative negligence rule that would emerge from the tam half-damages case differs from a standard comparative negligence rule. Whereas a standard comparative negligence rule requires an inquiry into the amount of actual comparative negligence of the victim, the tam half-damages rule stipulates categorically, and without an inquiry, that the victim is deemed to have been 50% comparatively negligent.
Understood this way, Jewish law’s tam half-damages rule parallels the old law of admiralty (the body of maritime law) governing a collision between two ships both of which were deemed to have acted negligently. See Prosser op. cit., p. 471 (“The original English admiralty rule divided the damages equally between the negligent parties…. The American courts followed the equal division rule in admiralty law until 1975.”) One possible explanation for this categorical stipulation of an equal split is that a rigorous inquiry into the actual percentage assignment of fault can be exceedingly difficult, if not impossible. Thus, because of the difficulties in administrating a pure comparative negligence rule, it may be reasonable to adopt a general rule of equal division for cases of comparative negligence. For an application of this type of reasoning to the case of joint tortfeasors, see Shulchan Arukh Choshen Mishpat 383:4 (“אם אין ידוע כולם משלמים בשוה”). See also supra, n. 10
In any event, there is scant textual evidence to support Sinai and Shmueli’s reading of Moreh Nevukhim 3:40.
It is true, as we noted in our previous article, that Rambam appeals to the principle of contributory negligence to explain why there are no damages for “tooth and foot” (“שן ורגל”) in a public domain. Rambam explains that for tooth and foot damages in the public domain, the victim is deemed to have been negligent by leaving his property in the public domain, and therefore cannot recover damages: “[For] he who puts a thing in a public place is at fault toward himself and exposes his property to destruction.” Moreh Nevukhim 3:40. Cf. Contributory Negligence in Jewish Law, op. cit. n. 23.
It is also true, as Sinai and Shmueli note, that Rambam’s discussion of half damages for a tam ox immediately follows his discussion of tooth and foot in a public domain. Moreh Nevukhim 3:40.
Yet to derive from this juxtaposition, as Sinai and Shmueli do, that the tam half damages rule must be grounded in considerations regarding the victim’s negligence is problematic for several reasons. First, Rambam never explicitly applies the logic of comparative or contributory to the case of tam half damages. Second, in the passage at issue, Rambam appears equally interested in the full damages of a mu’ad ox, implying no connection between the tam rule and prior discussion of the tooth and foot rule in the public domain.
The entire passage reads as follows:
One is free from responsibility [for the damage caused by] a tooth or a foot in a public place. For this is a matter with regard to which it is impossible to take precautions, and also damage is seldom caused in this way. Moreover he who puts a thing in a public space is at fault toward himself and exposes his property to destruction. Accordingly one is only responsible for [damage caused by] a tooth or foot in the field of the injured party.
On the other hand, damage caused by a horn and similar things regarding which precautions can be taken in all places and with respect to which those who walk in public places cannot take care, the law applicable to it—I mean the horn—is one and the same in all places. There is, however a distinction that is made between an animal that is docile and one about which its owner has been warned. If the act is exceptional, the owner is held responsible only for half the damage; if however, the animal that causes the damage continually does similar things and is known for this, the owner is held responsible for the whole of the damage. Moreh Nevukhim 3:40.