Topics in Talmudic Logic, Lecture 23
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Table of Contents
- The framework of the series and the hierarchy of temporal possibilities
- The Rashba’s responsum: when the law of bereira applies
- Eruvin, twilight, and applying bereira retroactively
- The distinction between retroactive and retrospective bereira
- Condition as backward causal influence in time versus bereira as marking
- Bereira, knowledge, logical determinism, and truth value
- Rashi and the Rashba according to the view that there is no bereira: “perhaps he drank terumah” versus “untithed produce retroactively”
- Certain doubt, kiddushin not fit for marital relations, and quantum superposition
- The Ritva’s question and a choice that decides an undecided state
- Nachmanides: the structural difference between condition and bereira, and implementing bereira through two conditions
- A condition dependent on will and choice, and its connection to the dispute over bereira
Summary
General Overview
The text places the topic of condition at the highest and most problematic level of backward influence in time, because a future event functions as a cause that produces a result in the present, and therefore it cannot truly be retroactive, only “from now on, retroactively,” in Rabbi Shimon Shkop’s formulation. It sharpens the point that bereira is different from condition, because bereira is about determining retroactively what already takes effect now by marking a specific object on the basis of a future event. Therefore, according to the view that there is bereira, there is no fundamental distinction between retrospective and retroactive use. The text grounds this in the Rashba’s responsum, which defines bereira as relevant only where the validity of the legal effect depends on “the matter becoming clarified” retroactively, and in the comparison between Rashi’s and the Rashba’s interpretations according to the view that there is no bereira, leading even to a proposed description in terms of “superposition” in understanding halakhic states. It concludes with Nachmanides, who formulates a clear structural rule distinguishing bereira from condition, and adds that cases dependent on will and choice may get drawn into the dispute over bereira even when they look like an ordinary condition.
The framework of the series and the hierarchy of temporal possibilities
The text continues a series on the logic of time and places two central topics within a hierarchy of relations between a future event and a present state. The text says that condition is at the highest level, where a future event serves as a causal factor for a change happening now, whereas bereira is not like that. The text lists four levels: uncovering information that already existed but was unknown, dependence on a future event that is not a matter of choice, dependence on a future event that does depend on choice and judgment, and a level where the future causally produces the present.
The Rashba’s responsum: when the law of bereira applies
The Rashba was asked how someone acquires ownership when a person sells his fellow “one of his parcels of land without specification,” given that “we hold that there is no bereira.” The Rashba answers that not every case should be compared to the laws of bereira. He states that the rule of whether there is or is not bereira applies only when one must say, “it has become clarified that what is now was already so and had already taken effect from the outset,” because without that “it has no validity.” He brings examples such as one who buys wine from among the Kutim, “this is your bill of divorce from now if I die,” writing a bill of divorce “for whichever one I wish to divorce with it” with respect to writing it for her sake, and brothers who divided an inheritance. The Rashba explains that in the sale of one field out of ten there is no need for the acquisition to take effect from now; rather, it takes effect “at the time he gives him what he sold,” and therefore there is no time-reversal needed for the validity of the legal effect, so it does not belong to bereira.
Eruvin, twilight, and applying bereira retroactively
The Rashba adds to his examples the law of eruvin, where a person stipulates between an eruv to the east and an eruv to the west depending on the arrival of a sage. The text emphasizes that according to the Rashba this belongs to bereira because “the eruv must take effect at twilight,” and therefore if the sage arrives on Sabbath morning it is necessary that by virtue of that arrival it become clarified retroactively that at twilight “the eastern eruv took effect.” The text notes that this is unlike the sale of land, where there is no halakhic requirement that the legal effect occur before the object is actually defined.
The distinction between retroactive and retrospective bereira
The text proposes a conceptual distinction between “retroactive bereira” and “retrospective bereira,” illustrating it through eruvin as opposed to one who buys wine from among the Kutim. In eruvin, retroactive clarification is needed in order to satisfy the law of twilight, but the practical use is made only after the sage has arrived during the Sabbath. In the case of wine from among the Kutim, the use is immediate, because the drinker wants to drink on the Sabbath on the basis of a determination that from this point it becomes clarified retroactively which two log are terumah. The text says that the Talmud does not distinguish between these two kinds of bereira, and presents that as a problem in relation to the conception of condition, where retroactively functions only as “from now on.”
Condition as backward causal influence in time versus bereira as marking
The text connects the topic of condition to the idea of backward causality in time and brings the example of annulling a vow, where after the annulment “history changes,” but the application is only from now on. It argues that in condition the future produces the present, and therefore the result cannot take effect before the cause; only after the cause has occurred can one speak about retroactively in the retrospective sense. It argues that in bereira the future does not produce the legal effect but only marks which object the legal effect—produced by a present action—will apply to, and therefore one can understand how bereira can work even in a retroactive way.
Bereira, knowledge, logical determinism, and truth value
The text explains that bereira fits with a view that the information “exists” even if human beings do not know it, and even suggests that according to the view that there is bereira one need not be a determinist in the sense that the information already exists, because one can rely on a distinction between information and truth value. It uses the discussion of logical determinism to argue that the truth value of a statement about the future can already be fixed now even if the information about reality does not exist in a strong sense. It formulates the point that marking an object can be done by means of a description that is uniquely defined even if no one is presently able to point to the referent, just as a scribe can write a bill of divorce for a particular woman’s sake on the basis of a description that does not actually identify the woman in practice.
Rashi and the Rashba according to the view that there is no bereira: “perhaps he drank terumah” versus “untithed produce retroactively”
The text presents a basic difference between Rashi and the Rashba in understanding the view that there is no bereira in the case of one who buys wine from among the Kutim. Rashi explains that “with regard to every cup one can say that it is terumah and tithe,” and therefore “we are concerned lest he drank terumah,” in a way that portrays an existing legal effect that is not marked and therefore casts doubt on every act of drinking. The Rashba explains, “and if there is no bereira, it turns out that this person is drinking untithed produce retroactively,” in a way that portrays the absence of any valid terumah designation so long as there is no valid retroactive marking. The text concludes that these two readings offer two ways of understanding “there is no bereira”: for Rashi, the impossibility of marking backward in time, or for the Rashba, a view in which the future event is a causal component in applying the legal effect.
Certain doubt, kiddushin not fit for marital relations, and quantum superposition
The text brings Rabbi Shimon Shkop in tractate Kiddushin on one who betroths “one of my two daughters,” and defines this not as an ordinary doubt but as a situation in which “each and every one of the two women is betrothed to me with tenuous kiddushin,” in a structure of “certain doubt.” It applies this to understanding Rashi in the case of wine from among the Kutim and argues that this is not a standard doubt in which there is one defined object and we simply do not know which it is, but a structure in which the legal states themselves are undecided. It describes this in terms of superposition as “state A plus state B plus state C,” and adds the two-slit experiment and Schrödinger’s cat in order to illustrate quantum collapse through “measurement.”
The Ritva’s question and a choice that decides an undecided state
The text quotes the Ritva’s question: why shouldn’t the father, with the agreement of the man effecting kiddushin, choose one of the daughters and then “it will become clarified” that she is the betrothed one? It explains that this question makes sense specifically if we are dealing with superposition and not with factual uncertainty. It argues that in kiddushin of the type “one of the two” one can picture a “collapse” through agreed choice, but in bereira that depends on a defined future criterion such as “the one who will go out through the doorway first,” there is no room for free choice to replace the criterion, and therefore the decision is unavailable according to the view that there is no bereira.
Nachmanides: the structural difference between condition and bereira, and implementing bereira through two conditions
Nachmanides establishes a rule that in a case “where he made his condition in the act” regarding a defined object, even if the condition depends on the acts of others, the condition is valid and this is not bereira. He illustrates this with a bill of divorce written for a specific woman: “if she goes out through the doorway first… and if not, it shall not be a bill of divorce,” and sees this as a valid condition, unlike one bill of divorce intended for one of two women depending on who goes out first, which is bereira and subject to dispute. The text builds on his words an implementation of the idea of bereira through two bills of divorce or two eruvin, each of which is conditioned separately, and argues that this would work “according to all opinions,” because each document is directed at one object, and the only doubt is whether the legal effect will take hold on it, not which object it is.
A condition dependent on will and choice, and its connection to the dispute over bereira
Nachmanides adds that “one who makes it depend on the will of others or on his own will” does not accept the formula “when he wishes, the matter has become clarified and it takes effect from the first moment,” except according to the one who says there is bereira. The text connects this to the level at which the future depends on choice, and therefore “the information does not exist.” The text mentions the case of kiddushin “on condition that father agrees,” and explains why the Talmud connects it to bereira even though it looks like a condition, because dependence on will brings it into the domain where the question of whether “it became clarified” retroactively depends on the dispute over whether there is or is not bereira. The text concludes by linking the four philosophical levels to halakhic categories: retroactive clarification of a fact, bereira in a future non-volitional event, dependence on will as part of the dispute over bereira, and condition as backward causality in time.
Full Transcript
[Rabbi Michael Abraham] And we’re in the middle of the series on the logic of time. After I gave the general introductions, a bit about the logic and philosophy of time, we moved into—well, we have moved into—two topics. One topic was condition, where seemingly a future event acts and determines a state in the present, acts backward in time. And the second topic is bereira, which we started last time. And I said there’s a difference between these two topics, in terms of where they’re located in that hierarchy of possibilities that I described at the beginning. So today I want to sharpen that a bit more. Let me just say, by way of reminder, that in the lectures on condition we saw that condition is located at the highest level, or the most problematic level, of backward influence in time. And this is basically a situation in which a future event is a causal factor for a change that happens now. In other words, a cause located in the future produces a result that happens now. That is not the situation in bereira. And today we’ll also talk about the relation between condition and bereira; that’ll be part of this whole discussion. So I want to—last time when I spoke, I presented the concept of bereira through the sugya in Gittin, and we saw there—it’s quite a long and detailed sugya—we saw all kinds of distinctions and possibilities and disputes: whether there is or is not bereira, whether it depends on one’s own judgment, whether it depends on the judgment of others, all sorts of distinctions between condition and bereira, and I’m going to return to some of those today. Let’s begin with an interesting responsum of the Rashba. The Rashba was asked this question: The question was, if someone sells his fellow one of his parcels of land without specification, and we hold that he gives him whichever one he wants, how does the buyer acquire it? For we hold that there is no bereira. Right? Someone goes and sells his fellow one of his lands. Let’s say he has ten parcels of land, one of them, without specifying which one. And again, this is not a case where there is a defined parcel and we just don’t know which one it is, but rather there is no parcel at all that has been defined. So the rule, says the Rashba, is that he gives him whichever he wants, whichever parcel he wants. The Rashba asks: how does he acquire it? After all, the transfer of ownership was made regarding an undefined, unspecified piece of land. So how did the buyer acquire the parcel that the seller later decides to give him? For we hold that there is no bereira. We rule in Jewish law, by the way—and maybe this is in the background here—that in rabbinic matters there is bereira, and in Torah-level matters there is no bereira. That’s what emerges from the Talmud at the end of tractate Beitzah. And the commentators have a big question about how to explain that ruling itself. Some want to say that the question of whether there is or is not bereira remained unresolved. So in rabbinic matters we are lenient, and in Torah-level matters we are stringent. It’s not that we rule one way in Torah-level law and another way in rabbinic law. Rather, we rule that the question of bereira remains in doubt; therefore in rabbinic matters we are lenient and in Torah-level matters we are stringent. Now, usually to be lenient means to say that there is bereira. For example, I’ll just remind you of one of the cases we discussed last time: one who buys wine from among the Kutim. In that case I have a jug of wine and I want to drink from it, but I can’t separate terumot right now—say it’s Sabbath now. So I say that the two log that will remain after Sabbath, those are what will be terumah. And according to the one who says there is bereira, I can start drinking now, because there are already two designated log within the jug. I drink, and everything I drink is obviously not the two log that will remain after Sabbath, and therefore what remains after Sabbath are in fact the log of terumah. And the rest I can drink as ordinary non-sacred produce. Here, saying there is bereira is the lenient position, right? Because saying there is bereira means terumah has been separated and therefore I can drink. Saying there is no bereira is the stringent position. No bereira means there are no log of terumah here, and therefore I can’t drink. So some of the medieval authorities explain that the Talmud’s ruling that in rabbinic matters there is bereira and in Torah-level matters there is no bereira is basically just an application of the rule: in rabbinic doubt we are lenient, and in Torah-level doubt we are stringent. Leniency means there is bereira. Stringency means there is no bereira. The point is that it’s not always like that. Sometimes the position that there is bereira actually turns out to be the stringent one rather than the lenient one. According to that approach, then, it’s really not always correct to say that in rabbinic matters there is bereira; rather, in rabbinic matters we choose the more lenient option. Usually the more lenient option is that there is bereira, but not always. Some say no: in rabbinic matters there is bereira, and in Torah-level matters there is no bereira. Those are two separate rulings. And that, by the way, is the accepted approach—two separate rulings: in rabbinic matters there is bereira, and in Torah-level matters there is no bereira. The questioner to the Rashba here assumes that since this is a Torah-level question—whether the land is acquired or not acquired—the rule is that there is no bereira, because this is Torah-level. Therefore he asks: how can one acquire such a field, one out of ten? So in his responsum the Rashba answers as follows: But what you compared in bringing these matters under the laws of bereira and then raised difficulties from one to another does not seem correct. For the law of whether there is or is not bereira applies only in a case where we need to say that it has become clarified that what is now was already so and had already taken effect from the outset, because if we do not say that it has become clarified, then it has no validity, since we need that retroactive clarification in order for the thing to stand. Like the case of one who buys wine from among the Kutim, where he separates after he has drunk, and if there is no bereira it turns out that this person is drinking untithed produce retroactively. And likewise in the case, “This is your bill of divorce from now if I die,” where if there is no bereira then it is a bill of divorce after death, since it only becomes a bill of divorce after he dies. And likewise in the case where the husband says, “Write a bill of divorce for whichever wife I wish to divorce with it,” where we need it for the very root of the matter, namely the time of writing, because we require that it be written for her sake. And similarly with brothers who divided an inheritance, where according to the one who says they are inheritors, we need bereira. What does that mean? The Rashba is basically saying this: all the questions of bereira are questions where we need something in the future to determine a reality in the past—always. In other words, there has to be some kind of movement backward in time. For example, in the case of one who buys wine from among the Kutim, the two log that will remain after Sabbath become clarified as terumah already now, because after all I want to drink the wine already now, not after Sabbath. If I wanted to drink the wine only after Sabbath, then this law wouldn’t depend at all on the law of bereira. I separate the two log that will exist after Sabbath, and when I separate them they will be terumah, and then I’ll drink. What’s the problem? That doesn’t depend on the dispute whether there is or isn’t bereira. When does it enter that dispute? In a case where I want to rely on it and drink the wine already now. Why? Because then the question is whether the matter becomes clarified from the future retroactively—back to now—or not. That’s the dispute over whether there is or isn’t bereira. And the same is true of “This is your bill of divorce if I die,” and likewise with someone who writes a bill of divorce—sorry, I said wine—for one of his wives, because at the time of writing the bill of divorce has to be written for her sake. So if it becomes clarified in the future, whichever one goes out first through the doorway, for example, then that has to determine the state in the past—on whose behalf the bill of divorce is being written right now. Therefore it depends on the question whether there is or isn’t bereira. But in the acquisition of the field—let me remind you again what the question was—someone sold his fellow one of his fields and didn’t specify which one. Fine. So what does the law say? Take one of the fields and give it to him. When does it become his? From now, from the moment he said it? No—from the moment I give it to him. There’s no reason at all to assume that the acquisition takes effect from the moment he spoke. The acquisition takes effect from the moment I give it to him. He performs an act of acquisition and acquires the field. So the Rashba says: what does that have to do with bereira? All questions of bereira are cases where a future event determines a state backward in time, a present state. With land, true, right now there is no defined parcel that I sold you, but there’s also no need to define it right now. It only has to be defined from the moment I give it to you. So what’s the problem? It has nothing to do with bereira, there’s nothing here that needs to operate backward in time. Okay? That’s how the Rashba explains it.
[Speaker B] Just one question: if I die—isn’t that a condition? Is that bereira?
[Rabbi Michael Abraham] We’ll get to that. I already noted that at the end of the previous lecture. We’ll discuss it.
[Speaker B] Condition or not?
[Rabbi Michael Abraham] We’ll discuss it, we’ll discuss it. The Talmud presents it as bereira, even though on the face of it, it’s a condition. The Rashba sums up; he says like this: And I give you a great rule: the law of bereira applies only in a case where, if it is not written, one cannot divorce with it. Or likewise in “if I die”—yes, “if I die”—where if there is no bereira, it turns out to be a bill of divorce after death. And in eating and drinking—yes, that’s the case of one who buys wine—where if there is no bereira he cannot drink, because it would be untithed produce. And if he comes from the east—if there is no bereira, it turns out there is no eruv here and it is impossible for him to walk. He means the sugya in tractate Eruvin, which we didn’t cover, on folio 37. The Talmud there discusses someone waiting for a sage to arrive on the Sabbath in some place, from the east or from the west. A person is in town and doesn’t know whether the sage will arrive from the east or the west. So he needs to make an eruv because he wants to hear the sage’s lecture. What does he do if he doesn’t know on which side the sage will arrive? So the Talmud says he places two eruvin, one to the east and one to the west, and he makes a condition: if the sage comes from the east, the eastern eruv will take effect; if the sage comes from the west, then the western eruv will take effect. Now apparently here too there should be no need to invoke bereira. Why? Because when the sage arrives, then the eruv on that side will take effect and then I’ll use it; after all, only then do I walk. So what’s the problem? The Rashba says: no, that’s not right, because the eruv has to take effect at twilight. That’s part of the laws of eruv. If the eruv doesn’t take effect at twilight, you can’t use it later. Since that’s the case, then when the sage arrives from the east, retroactively—he arrives in the middle of Sabbath—retroactively, at twilight, the eastern eruv already took effect. True, when I actually go I only go after the sage has arrived, but the eruv took effect retroactively, and that’s why this belongs to the topic of bereira. That is unlike the question of the parcels of land, which has nothing to do with this—that’s what he says. But in a matter whose validity does not depend on bereira, such as sale, gift, charity, or an offering brought from a vow, the law of bereira does not apply, because at the time he gave him what he sold, even according to the one who says there is no bereira, the law of bereira does not hold things back, since it can be valid without bereira. And likewise with “It is incumbent upon me to bring a burnt offering,” and everything similar to that. Right—if I give you land, from the moment I gave you the land it’s yours; nothing needs to be clarified backward. So what does that have to do with bereira? The fact that when we spoke I didn’t define a specific parcel out of the ten—that doesn’t matter. It has nothing to do with bereira, because bereira is only when I don’t define something but I want a future event to come back and define it as of now. But if I don’t define something and I don’t need it to be defined as of now, it’ll be defined when it gets defined. Then there’s no problem at all. That has nothing to do with the topic of bereira. That’s basically what the Rashba is claiming. There’s a possible distinction one could make between two kinds of bereira. Up to this point, this is just the definition of bereira: bereira always works backward in time. That’s what the Rashba taught us. But even when I talk about something that works backward in time, I can talk about it in two ways. Let’s call it—in the language lawyers use—retroactive bereira and retrospective bereira. What do I mean? Take, for example, the bereira in Eruvin, where the sage may arrive from the east or from the west. The Rashba says this belongs to the law of bereira. Why? Because the eruv has to take effect at twilight. So if the sage arrives from the east on Sabbath morning, then I need the eastern eruv to have taken effect back at twilight. Even though he arrived on Sabbath morning, that is supposed to cause the eruv to have taken effect at twilight—the eastern eruv took effect at twilight. But when do I use that clarification? On Sabbath. Only after the sage has arrived. After the sage arrives from the east, I understand that he’s there, and then I go to him, right? In other words, the use I make of the process of bereira is not retroactive. Something retroactive is required here in order for the eruv to take effect, because it has to take effect at twilight, and at twilight the sage still hadn’t arrived anywhere.
[Speaker C] But the use is on Sabbath.
[Rabbi Michael Abraham] The use of the eruv is made only after the clarification has already taken effect. Where do we have another kind of case? For example, with one who buys wine from among the Kutim. I now want to designate the two log that will remain after Sabbath, and on that basis drink now. So the use is not only that I need the terumah to take effect now, but also—the use of the fact that terumah has been separated, I make now, not only after Sabbath when there are already two log that will have been clarified. Do you understand the difference between the two cases? In the case of Eruvin, the clarification is retrospective and not retroactive. It’s retro in the sense that the eruv has to take effect at twilight, but it’s prospective in the sense that although it happens retroactively, my use of it is only from that point forward. By contrast, in the case of one who buys wine from among the Kutim and separates terumah, it’s retroactive. Why is it retroactive? Because I also need to make use of it on Sabbath, even though the clarification will occur only after Sabbath, because after all I want to drink the wine now. Therefore this is actually retroactive bereira. Now it becomes clear—literally “becomes clarified,” because that’s a double meaning—that the Talmud makes no distinction between these two processes of bereira. Whoever says there is retroactive bereira also has retrospective bereira, and whoever does not accept retroactive bereira also does not accept retrospective bereira. As far as the Talmud is concerned, it makes no difference at all. Now understand, I want to remind you of what we said about condition. We’re starting to tie up the loose ends. In condition, I said—if you remember—I gave the example of annulling a vow, where I go to a sage, the sage annuls my vow, and then the vow is permitted retroactively. If I had violated the vow before I went to the sage, and afterwards I went to the sage and he annulled the vow, then the annulment works retroactively. And we discussed there Rabbi Shimon—if you remember—that this is “from now on, retroactively.” What does that mean? If a religious court flogged me after I had eaten what was forbidden by that vow, it acted perfectly properly, no problem at all. But after the sage annulled it, now if the religious court sits and judges the matter, it will no longer flog me. Why? Because from this point onward, history changes. The vow was never in existence. Before the sage annulled it, the vow actually took effect. After the sage annulled it, he uprooted it retroactively. That is really retrospective, right? Because the retroactive clarification helps only from now on; it doesn’t really help retroactively in application. In other words, it occurs retroactively, but its applications are only from the moment it occurred. That’s what I’m calling here retrospective. Right? In bereira, by contrast, it doesn’t bother the Talmud at all if it is also retroactive and not merely retrospective. And the question is how to explain that. Why does it make no difference whether it is retroactive or retrospective? I want to explain—
[Speaker B] The basic question is whether there is or isn’t bereira.
[Rabbi Michael Abraham] Right, but one could have said—
[Speaker B] Either this or that or that, but there was—
[Rabbi Michael Abraham] —one could have said, as with condition, that with condition I say it does indeed happen retroactively, but only from now on, retroactively. But in bereira I have no problem saying that it happens retroactively, period—not from now on, retroactively. In Eruvin it’s from now on, retroactively, but with terumah it’s really retroactively. How can something happen retroactively if with condition that doesn’t happen? With condition it’s impossible for it to happen retroactively. So why doesn’t it bother me in bereira that it happens retroactively? For that I need the one who says there is bereira, of course. For the one who says there is no bereira, it really does bother him. But the one who says there is bereira does not distinguish between retroactive and retrospective. And the question is how to understand that. In order to understand that, let’s try for a moment to think about the concept of bereira—I’m tying up another loose end here—in terms of the hierarchy I built at the beginning. Wait just a second. I talked, if you remember, about several kinds of relations that can exist between a future event and the present time. There can be—and let me remind you again of the hierarchy because it accompanies us throughout—there are basically four such relations, one above the other. The first relation is when a son is born to me in a distant place, and I don’t know whether it’s a boy or a girl. A child was born; I don’t know whether it’s a boy or a girl. When I get home I see that it’s a boy. Obviously it becomes clarified retroactively that it was a boy from the beginning. It’s not that only now, suddenly, I see that this thing is a boy. Okay? That was the state from the outset. So what was the issue up until now? Up until now, I simply didn’t know that. That’s all. Now the information has become known to me. So here, nothing actually happened retroactively, right? This is a case about which there are no dilemmas and no problem. It’s not really called retroactive at all; it’s just information that I lacked and then it was revealed to me. A different case is when I make something depend on a future event, like with the conditions we discussed, or with bereira. Write it for the one who will go out first through the doorway. The event of her going out first through the doorway will happen tomorrow. And I want the bill of divorce to be written today for the sake of the one who will go out first through the doorway tomorrow. So the future event determines who is the woman for whose sake the bill of divorce is being written now. This information, in principle, does not exist, because it hasn’t happened yet. This is not like the son who was born to me, where obviously the information exists—God knows it. Fine? Here the information does not exist because the event has not yet happened. That’s the second state. I said that regarding this state one could say that even here the information exists, only nobody in the world knows it. For example, unlike my son who was born, where his mother does know that it’s a boy and not a girl. I, being far away, don’t know. So there the information not only exists, it’s also known to human beings; I just happen not to know it, so what? That has no significance. Here one can formulate it in two ways. One can say that since I am making it depend on a future event—whichever one goes out first through the doorway, or whether the sage comes here or there—then the information right now, namely where the sage will come or which woman will go out first through the doorway, simply does not exist at the moment. That’s one way to formulate it. A second formulation is: the information does exist—God knows it—only no human being knows it. It’s not just that I personally don’t know it; rather, no human being knows it. But I still claim that perhaps the information does exist. It’s not true that the information does not exist; it’s just not known to anyone. God can know what will happen in the future, at least if it’s a deterministic matter.
[Speaker D] There’s still something from last week that bothers me a little. I understood well from you the difference between choosing and picking, what you explained, but I still have a hard time with your saying that the information exists with God regarding who will leave the house first. Because until she goes out there are so many factors, and they also include judgment and choice—
[Rabbi Michael Abraham] One little step like that of—
[Speaker D] —free choice, and then He wouldn’t know what will happen.
[Rabbi Michael Abraham] You’re absolutely right. If the matter includes judgment and choice, then it belongs to the third level. The third level is when the future events are events of judgment or choice, for example, on condition that father agrees. Or if the one who goes out first through the doorway is doing so as a matter of choosing rather than merely picking—she’s going out to do a commandment, not just because she feels like getting some air. Fine. It doesn’t matter, I’m not classifying the cases right now, I’m only describing the types. So the third level is when I make something depend on a future event, and that future event depends on free choice. Why is that different from the previous level? Because here, according to all views, the information does not exist. Even God does not know it. Okay? That’s the third level. The fourth level is not essentially different from the first three, except that on the fourth level the future event causes the present state. Whatever the future event may be—choice, no choice, it doesn’t matter—but the point is that something future causes the present state. In other words, backward causality in time is happening here. I explained that in conditions we see this as the fourth level. A condition, as Rabbi Shimon Shkop explained, is something in the future causing what happened now. Therefore Rabbi Shimon Shkop says this cannot operate retroactively, only retrospectively. It happens backward in time, but backward in time only hypothetically. I can make use of it only after it has happened. Fine, that’s basically what he claims. But in bereira we see in the Talmud that this doesn’t bother it. It doesn’t care whether it’s retroactive or retrospective. The question is why. And my answer is that bereira belongs to the first and second levels, not the fourth. What do I mean? My claim is that in bereira the information actually exists. Right now. I just don’t know it. And therefore, according to the one who says there is bereira, that view is basically just saying: I make use of existing information that I don’t know, in order to mark the woman for whose sake I’m writing the bill of divorce, or the eruv that will take effect, or the log of wine that I want to be terumah. That can be done. Why? Because here the future event does not cause the present state. What causes the bill of divorce—or the validity of the bill of divorce? The scribe’s writing, not the woman’s going out through the doorway. Right? The scribe’s writing causes the bill of divorce. I just need to indicate to the scribe which woman he should have in mind when he writes the bill of divorce. The indication I give the scribe relies on a future event. But it’s not that the future event causes the validity of the bill of divorce, that it is the causal factor that makes the bill of divorce valid. No. The causal factor, what makes the bill of divorce valid, is the writing of the scribe and his intention. It’s just that when I want to indicate to him the woman he has to have in mind, that indication is made by means of a future event. That’s the point. Marking—according to the one who says there is bereira—can be done backward. Backward causality, maybe not. But marking can be done backward. I’ll say even more than that. Suppose the information doesn’t exist at all, and even God doesn’t know it, for the sake of the discussion. Even then, in my opinion, there is still room for the view that there is bereira, and the one who says there is bereira does not have to be a determinist. Why? Let me remind you of another part of the introduction—you see now, I’m using everything we talked about up to this point in this topic. Now I’m tying together all the loose ends. I’ll use another point from the introduction I gave about logical determinism. I said in the discussion of logical determinism that when I say today the sentence “tomorrow there will be a naval battle,” that sentence is already true today, even though perhaps the information doesn’t exist because it depends on people’s choice whether they choose to make a naval battle or not. But the truth value of the statement is already fixed now. And there I distinguished between assigning a truth value to a proposition and saying that the reality the proposition describes—the information about it—already exists today. Those are not the same thing. Information may not exist before the event occurs, at least if I am not a determinist, but the truth value can be determined from the future back to the past. Why? Because this is not a causal relation. The relation between the event and the truth value of the statement describing it is not causal relation but definition. The truth value of the statement is not an event in the world. Causes apply to things that happen in the world. Things that happen in the world have causes. An event happened, there’s a cause that brought it about. But the fact that the truth value of this proposition is “true”—we use that word, but it’s misleading, because it’s not correct to say that the cause of the proposition being true is that tomorrow there will be a naval battle. No. If there will be a naval battle, then the proposition will be true. That’s a condition, not a cause. Remember my introduction about causality? This is only the dimension of condition. It’s “if, then.” It’s not a cause. And “if, then” can also work backward in time. Remember Steinitz’s Athena paradox? There I showed that “if, then” is symmetric with respect to time. Only causality goes from past to future. Therefore, when I speak about bereira, I’m not speaking at all about something causal. If I’m not speaking about something causal, then why should I care that the future determines the past? I’m merely using a future event to mark a present object. Marking is a definition. It does not require any information. It’s a definition. Let me formulate it differently. Look. Suppose I were to say now to the scribe: the woman who will go out first tomorrow through the doorway is Rachel the younger. Obviously I don’t know that. But suppose I said that proposition. And suppose that tomorrow Rachel the younger really is the one who goes out first through the doorway. Was the proposition I said true? Yes. Obviously yes. Right? How do I know? Compare the content of the proposition to the reality the proposition describes; if there is correspondence, then it is a true proposition. It doesn’t matter what I knew, right? The proposition is true regardless of what I knew. What I want to say is that it’s possible to define the woman for whose sake the bill of divorce is written by means of the truth value of a proposition. You don’t need information. You need the truth value of the proposition to be true. I want to put a check mark on the woman. So I can mark the woman by saying she’s the taller one. I can mark her by saying she’s the darker-complexioned one. And I can mark her by saying she’s the one who will go out first through the doorway tomorrow. What difference does it make? These are just different ways of marking. And if you ask me whom the marking marked—it marked Rachel the younger. The fact that I don’t yet know that—tomorrow I’ll know. But it marked her already now. Because marking does not depend on information. Marking depends on the truth value of the sentence. And the truth value of the sentence already exists today. I think I explained this to you last time. I said that when the scribe writes for the sake of one of my wives, after all he doesn’t know either of them. He may not know them. That doesn’t prevent him from writing the bill of divorce, right? So even if I describe her to him as the darker-complexioned one, that won’t help him, right? He still doesn’t know them. So what difference does it make? Then I describe her as the one who will go out first through the doorway tomorrow—what’s the difference? The main thing is that I have singled out a very specific woman toward whom the writing of the bill of divorce is directed. That’s all. Have I singled out a specific woman? Unambiguously yes. The woman who will go out first through the doorway tomorrow. The fact that neither of us can yet point to that woman—so what? Even if I myself knew how to point to her, the scribe still wouldn’t know how to point to her, because he doesn’t know them. So suppose I said: write it for the darker-complexioned one. I know which one is darker-complexioned, but the scribe doesn’t know them so he doesn’t know. But that’s fine. That has nothing to do with bereira. Why is it fine? Toward whom is the scribe directing his intent? Toward the one who is darker-complexioned, right? In other words, it’s enough that I marked for him in an unambiguous way the woman for whose sake he is writing the bill of divorce. This is a bill of divorce written for a specific woman. So what if he doesn’t know her? If that’s so, says the one who holds there is bereira, why shouldn’t I be able to mark a woman on the basis of a future event? True, in this case not only does the scribe not know which woman is marked here, I don’t yet know either, so what? After all, the intention that matters is the scribe’s intention, not mine. So what difference does it make whether I know or don’t know? What matters is how I indicate her to the scribe.
[Speaker B] The scribe is the one divorcing? The scribe isn’t the one divorcing—the husband is the one divorcing. The husband’s intention is really the relevant parameter.
[Rabbi Michael Abraham] No, because the scribe has to intend to write it for the sake of the woman, not the husband. The scribe who writes the bill of divorce—we’re not talking about the act of divorce, we’re talking about writing the bill of divorce. The writing of the bill of divorce is what makes it valid. The woman is not yet divorced, but the bill of divorce is valid to divorce with if it was written for the sake of the woman being divorced. So the intention that matters is the scribe’s intention, not the husband’s. Okay? Therefore you separated the husband—
[Speaker B] —from his intention? He has to know, throughout the writing of the bill of divorce, to whom you’re giving this bill of divorce.
[Rabbi Michael Abraham] I didn’t understand. At the time—
[Speaker B] —of writing the bill of divorce, the husband—
[Rabbi Michael Abraham] —has to tell the scribe something definite.
[Speaker B] He has to know to whom.
[Rabbi Michael Abraham] No, why does the husband need to know? Who said he has to know? If I have two wives that I never knew at all, okay? I also didn’t know them; an agent betrothed them to me. Now I divorce the one the agent betrothed first. Hello, are you with me? I betroth the one the agent betrothed to me first. I myself don’t know who that is. But there is already one woman there; she is well-defined. The agent knows who she is. Is that okay? The answer is yes. It doesn’t depend on retroactive clarification. That’s the first mechanism. The first mechanism is like when a child is born to me and I don’t know who he is. Once I get there, I’ll know who he is. Here too it’s the same thing. The information exists; the agent knows it. I don’t know it. So what? But I defined a woman in an unambiguous way, so that if I go to look for which woman the bill of divorce was written for, I’ll be able to point to one specific woman unambiguously. I’ll simply ask the agent whom he betrothed first, and that will be the woman I divorced. There’s no problem at all.
[Speaker B] Maybe I’ll give you another example? What if the agent dies, for instance? There is a presumption that an agent carries out his mission. Right.
[Rabbi Michael Abraham] But—
[Speaker B] The moment he came, and I came and defined for him a certain woman, then I know that that particular woman got married or didn’t. If I didn’t define for him—
[Rabbi Michael Abraham] I didn’t define for him whom to betroth first and whom—
[Speaker B] second.
[Rabbi Michael Abraham] What? I didn’t define for him whom to betroth first and whom second.
[Speaker B] I’m talking about one woman. Just one woman.
[Rabbi Michael Abraham] I’m talking about two women, though. Our case is that the agent betrothed two women: Rachel the older and Rachel the younger. One of them he betrothed in the morning and the other in the afternoon. I sent him as an agent to betroth two women for me, okay? Now the next day I said, you know what, I don’t have the energy, I only want one wife. I take a scribe and tell him: please write me a bill of divorce for the one who was betrothed to me first. I don’t know who that is. The agent didn’t tell me. Is the bill of divorce valid? Yes. Obviously yes. It doesn’t depend on retroactive clarification. There is one woman who is very well defined as the one who was betrothed to me first. So what if I don’t know who she is? Now if I do know, that also makes no difference, because the one who needs to know is the scribe. And if that doesn’t get in the way, then apparently we don’t need my knowledge, or the scribe’s knowledge, or anybody’s knowledge. What is needed is that the woman be defined in a univocal way. Right? That’s what’s needed. Even if none of us knows who she is. If so, then the one who holds that there is retroactive clarification says that a woman who is defined on the basis of a future event is also defined in a univocal way. We’ll just wait till tomorrow and then we’ll know who she is. So what difference does it make? But once we know who she is tomorrow, that will also clarify for us that she was the correct one today as well. Right? Exactly. All I did was mark one woman out of two. Why is it forbidden to mark on the basis of a future event? I can mark her based on her color, based on her height, or based on the fact that tomorrow she’ll be the first to go out through the doorway. What difference does it make? Okay? Therefore, once we’re dealing with a process of marking, the one who says there is retroactive clarification has no problem with the marking using a future event. And that’s the difference between retroactive clarification and a condition. A condition is backward causality in time. Backward causality can happen only retrospectively, not retroactively. What do I mean? As long as the cause has not yet occurred, the effect cannot take place. If the annulment of the vow was on Wednesday—I vowed on Sunday, and the annulment was on Wednesday—then the vow cannot already have been annulled on Tuesday. Because the annulment hadn’t happened yet. True, after it happens it takes effect retroactively. Remember the time-travel discussion with all the introductions I gave, with two timelines and all the definitions? There I defined how this thing works. It can happen. But before I even went to the sage, obviously on Tuesday if I violated the vow then I am liable to lashes. Because the annulment had not happened at all yet. But all that is in a condition. A condition is the fourth mechanism. It’s the mechanism in which the future event causally brings about the present state. That cannot happen retroactively. Only retrospectively. Okay? But in the mechanism of retroactive clarification, the woman’s going out through the doorway, or the remaining two logs of wine at the end of the Sabbath, or the sage’s arrival from the east or from the west on the Sabbath—all these do not bring about the event, they only mark which of the two objects I intended the legal effect to apply to. The eastern eruv or the western one. Woman A or woman B. These two logs or two other logs. Okay? And therefore there is no problem at all if that also happens retroactively. Because once these two logs are marked, then they are also terumah from now, and I’m allowed to rely on that now even though the end of the Sabbath hasn’t come yet. What made them terumah was the separation of terumah that I did now. The definition. Only the definition—which two logs will be terumah—is determined by the event at the end of the Sabbath. But the event at the end of the Sabbath does not create the status of terumah on those two logs. The one who does that causally is me, when I separate terumah now. Only what this legal status of terumah will apply to—that will be determined by the event at the end of the Sabbath. That’s just marking. Therefore the marking does not create the result. It is a condition for the result; it is not the cause of the result. Here is the difference in the Humean definition of causality. The future event here is the condition that defines the logs, or the woman, or the side from which the sage comes for the eruv, and so on. It is not the thing that creates the legal effect of the event, or the divorce, or the terumah. The legal effect is created by my action now. Okay? Therefore a future event that only marks the object to which the legal effect will apply—a marking can also be done by means of a future event, and I have no problem. I can use it right now. That is truly retroactive, not only retrospective. I can drink the wine now and rely on the fact that the two logs of terumah are already well marked, and terumah has already taken effect upon them, and I drink the wine. That is the view that says there is retroactive clarification. Okay? The view that says there isn’t—irrelevant. What? The one who says, according to the view that there is no retroactive clarification, this whole discussion is irrelevant. What do you mean irrelevant? That’s the dispute—whether there is or isn’t retroactive clarification. Irrelevant—what’s he supposed to do with the wine? No, no, there won’t be—it can’t be a case of conditional clarification. I didn’t understand. The one who says there is no retroactive clarification—so I can designate the wine now, for example, but I can’t drink until the end of the Sabbath. You can drink at the end of the Sabbath if you separate the two logs then. That’s it—but not from now. Meaning the clarification won’t take effect. Right. Fine—there is no retroactive clarification. Obviously. That’s the position that says there is none. Until now I was explaining the position that says there is. Yes, right. The one who says there is no retroactive clarification claims that a future event cannot even mark. Or, another possibility: even in retroactive clarification, the future event is the causal factor of what happened in the past, and therefore it cannot take effect backward. Two possibilities for understanding the one who says there is no retroactive clarification. Okay? Just one second. Now I want to remind you of something we saw in the previous lesson. Let me share again. I mentioned last lesson that Rashi, in several parallel passages, explains the one who says there is no retroactive clarification this way. Look. Rabbi Yehuda and Rabbi Yosei and Rabbi Shimon prohibit—they prohibit, meaning they prohibit drinking the wine in the Mishnah of one who buys wine from the Cutheans—until he actually separates from it, because they hold there is no retroactive clarification. So why is it forbidden to drink? Rashi says: regarding every cup, one must say that perhaps it is terumah and tithes, even from the very first one. Even the first cup I drank—you never know, maybe that was the cup of terumah. Even though it’s not the two logs that will remain at the end of the Sabbath, because obviously I drank it, so it’s no longer the two logs that will remain. But there is no retroactive clarification. So once there is no retroactive clarification, then the status of terumah applies to every pair of logs in the mixture. Not דווקא the two logs that will remain at the end of the Sabbath. Then Rashi is basically saying that at this point I am in a state of doubt, because the legal effect may apply to these two logs, or these two logs, or these two logs, and therefore I can’t drink any of them because perhaps I am drinking terumah. If you remember the language of Rashba that we saw above, look: “And if there is no retroactive clarification, it turns out that this one drank untithed produce retroactively.” What’s the difference between him and Rashi in explaining the position that there is no retroactive clarification? He goes differently from Rashi. “It turns out retroactively that it cannot be clarified—there is no retroactive clarification.” How would it be clarified? It turns out that this one drank… Exactly. That’s why there is no retroactive clarification. What is the difference between Rashi and Rashba in understanding the opinion that there is no retroactive clarification? According to Rashi, why is it forbidden to drink the wine if there is no retroactive clarification? Because maybe I am drinking terumah. According to Rashba, why is it forbidden to drink the wine? Because he is drinking untithed produce. According to Rashba, for the one who says there is no retroactive clarification, terumah does not take effect on any log at all. According to Rashi, even according to the one who says there is no retroactive clarification, terumah does take effect—just not specifically on the two logs that remain at the end, because it will not become clear which two logs. So I imposed the status of terumah on some two logs in the mixture. That means that Rashi and Rashba understand the position that there is no retroactive clarification differently. Earlier I explained the position that there is retroactive clarification, right? The position that there is retroactive clarification says I can use a future event to mark an object. Even a future event is a way of marking; there’s no problem. What does the one who says there is no retroactive clarification hold? According to Rashi, according to the one who says there is no retroactive clarification, the marking doesn’t work, right? The marking doesn’t work. On the other hand, if the marking doesn’t work, what does that mean? After all, I did the action that creates the terumah. I separated terumah. I just didn’t succeed in marking which two logs it applies to. So what follows? That it applies to one out of every pair of logs in the mixture. Because I failed to mark—I failed to mark the relevant two logs, right? So there is a status of terumah here because I separated terumah. The future event does not create the status of terumah. The one who creates the status of terumah is me, when I separate terumah. The future event only marks which two logs the status of terumah will apply to. According to the one who says there is no retroactive clarification, the marking doesn’t work. So if the marking doesn’t work, what’s the result? That there is terumah on everything, or there is terumah on any pair of logs you choose. There is doubt—maybe this is the terumah—therefore you can’t drink any of them, because perhaps these are the two logs of terumah. Right? Rashba apparently—and by the way this appears elsewhere too. Look, for example here in Chullin, Rashi there says: “Apparently Rabbi Yehuda does not hold of retroactive clarification and is concerned lest he drank terumah”—not untithed produce, terumah. Again, in another place Rashi says this in four, five, six places throughout the Talmud. So according to Rashi it is pretty clear that for the one who says there is retroactive clarification, the future event functions as marking, and marking can be done on the basis of a future event. For the one who says there is no retroactive clarification, he too agrees that the future event is only marking, but since the event that creates the status of terumah did occur—it occurred now, by my saying “the two logs will be terumah”—only I have no marked two logs, because the marking does not work backward, so the status of terumah applies to every pair of logs in the mixture. That is how Rashi understands the dispute. According to Rashba, if I didn’t mark any pair of logs, then nothing takes effect at all. What does that mean? That according to the one who says there is no retroactive clarification, he does not view the future event merely as an event of marking. It does not take effect at all. In his view it is a condition that—it is a cause, not only a condition. It is the cause thanks to which there is a status of terumah here. If the cause didn’t happen, then there is no status of terumah in the mixture. Which event is causative? The two possibilities that I explained, the two possibilities I suggested for understanding the dispute between the one who says there is and the one who says there isn’t retroactive clarification—that is simply Rashi and Rashba. Meaning, according to the one who says there is retroactive clarification, they both agree on the understanding. The understanding is that the event that creates the terumah is the present separation that I do now. The future event, such as leaving over two logs, only marks which two logs the status of terumah will apply to. On this both Rashi and Rashba agree, and therefore according to the one who says there is retroactive clarification, I have marked two logs, and those two logs are terumah, and I can drink all the rest. According to the one who says there is no retroactive clarification, here Rashi and Rashba already disagree. According to Rashi, the one who says there is no retroactive clarification accepts all the conceptual framework of the one who says there is retroactive clarification. He only claims that since there cannot be marking that happens backward, the status of terumah applies to every pair of logs. Because after all the status of terumah definitely applies here, because I did the act that imposes terumah. Only there are no two logs marked as the ones to which the act was applied. Therefore the act applies to every pair of logs in the mixture, and so we are in some kind of doubtful state. In contrast, according to Rashba, future marking—for the one who says there is no retroactive clarification—he disagrees with the one who says there is, because he claims that the future event does not merely mark. It does not take effect at all. It also contributes to the very imposition of the status of terumah itself. Without something specific being marked, you cannot impose the status of terumah. You cannot impose the status of terumah without something for it to apply to. Therefore the future event is a causal factor in the taking effect of terumah. Consequently, according to the one who says there is no retroactive clarification, there is no terumah at all. It is untithed produce; it remains untithed produce. In other words, Rashi and Rashba are exactly the two possible conceptions of the one who says there is no retroactive clarification. And that sums up everything we have done until now, because it means that according to Rashi in the responsum we saw, yes? He says that retroactive clarification is only when something happens backward. But still, that can only be when something happens backward not causally but only in terms of marking. A truth value of a statement, if you like. Okay? Therefore according to the one who says there is retroactive clarification, both Rashi and Rashba agree that it is when the future event marks a present object. According to the one who says there is no retroactive clarification, there are two ways to understand what he disagrees about with the one who says there is. Either he claims that even marking cannot work backward—and that is Rashi—or he claims, no, no, you’re not right, the one who says there is retroactive clarification: the future event is the causal factor for the taking effect of terumah, not merely the marker, and therefore I say it cannot work backward; there is no terumah. Why shouldn’t marking work backward? How does the one who says there is no retroactive clarification think? What’s the problem? As I said earlier, marking is a very neutral thing; the main thing is that there is an object I have defined univocally. What difference does it make that nobody knows which object this is? So either he claims that you cannot mark an object if nobody knows it; that isn’t called marking. Marking always requires that at least one person know the marked object, otherwise it isn’t called marking. Marking with invisible ink is not called marking. But it may be that he means to disagree and say that the one who says there is retroactive clarification thinks marking can work because he is a determinist. He claims that the information already exists now. And the one who says there is no retroactive clarification does not accept that. He claims that the information does not exist now—only the logical value exists now, but not the information—and a logical value is not enough to determine an object. You need information. Maybe that is the dispute. And the possibilities I described all along the way open up all the possibilities for understanding the dispute according to Rashi and according to Rashba, between the one who says there is retroactive clarification and the one who says there is not. Now I want to move for a moment and look a bit at the one who says there is no retroactive clarification. But the one who says there is no retroactive clarification according to Rashi. According to Rashi, this view says that the legal effect applies to two logs, and this is basically a state of doubt. Right? It’s a state of doubt. So if it were rabbinic, then one would expect leniency. So there should be leniency. Then I could drink, say, something that is obligated in terumah only rabbinically. So I can separate from it this way, right? Because it’s a doubt. And even according to the one who says there is no retroactive clarification—notice, not according to Jewish law, but according to the one who says there is no retroactive clarification—what does he himself think about rabbinic terumah separation? According to Rashi he should hold like the one who says there is retroactive clarification, right? That would come out stringent? No, the opposite, lenient. Because he would hold that there is a situation here where I may assume that what I’m drinking is not the two logs of terumah, because in a rabbinic doubt we are lenient. So therefore I can drink—even according to his own view I can drink, right? Are you with me? According to Rashba, no, because according to Rashba it is untithed produce. Even if it is rabbinic untithed produce, rabbinic untithed produce is also forbidden to drink. According to Rashi it is not untithed produce, it is doubtful terumah, and my whole problem is the doubt whether I am drinking terumah. If it is rabbinic terumah, then out of doubt I am allowed to be lenient. Now I want to argue that this is not correct. Even according to Rashi it is forbidden to drink, even if it is rabbinic. And the reason is that Rashi is not saying that there is a doubt whether these are the two logs that are terumah, or these, or these. This is quantum superposition. What Rashi wants to say is that every pair of logs is doubtful terumah. Not that there is doubt which pair of logs is the terumah, but rather that every pair of logs has upon it a faint status of terumah, or doubtful terumah. Therefore even if it is rabbinic, I am forbidden to drink it, because even rabbinic terumah is forbidden to drink. Each one of them is definite faint terumah. So I am forbidden to drink it even if it is rabbinic. These are not laws of doubt; these are laws of certainty. I think I mentioned the Talmudic issue of betrothal not fit for intercourse in one of the previous lessons—I don’t remember whether in this lesson or the previous one, I don’t know. “Divorced or not divorced” fits this much better. I didn’t understand. No, that’s something else. Yes, there it fits much better. Right, there it’s really exactly this, but I don’t remember whether I mentioned it here. I’ll say it briefly. Rabbi Shimon Shkop too, in Sha’arei Yosher, discusses a case where a man gives a perutah to a father and wants to betroth one of his two daughters, without defining which one, like the land cases in the responsum of Rashba that we saw. Fine? Now there is a problem because they are two sisters. Let’s say these are Rachel and Leah. If Rachel is betrothed to me, then Leah is my wife’s sister. If Leah is betrothed to me, then Rachel is my wife’s sister. Since that is so, I cannot have relations with either of them, because I don’t know which one is my wife, Rachel or Leah, so any one I want to have relations with—it may be that in truth the other one is my wife, and this one is my wife’s sister, with whom I am forbidden to have relations; she is a forbidden relative. Okay? This is called betrothal not fit for intercourse. Okay. Now a question arises here: according to Maimonides—sorry—regarding a Torah-level doubt Maimonides is lenient. So what’s the problem? I can have relations with her. I am in doubt whether she is my wife’s sister or not; I can have relations with her. Why does the Talmud say that this is betrothal not fit for intercourse? My answer is maybe that if he has relations with her then she becomes his wife at that very moment? Even better—then it’s completely fine. Then certainly I can have relations with her. So there’s no concern at all that she is my wife’s sister. That would already be a quantum collapse; in a moment I’ll comment on that. The point is, I claim—and this is basically what Rabbi Shimon Shkop says, though he doesn’t say it as an answer to a question on Maimonides, that’s my point—but Rabbi Shimon Shkop establishes the principle. He says this is not a state of doubt at all. It’s called a definite doubt and not a doubtful certainty. What does that mean? A state of doubt is when one of them is betrothed to me and I just don’t know which. Here there is not one defined woman who is betrothed to me. The doubt is in reality itself; even the Holy One, blessed be He, does not know which of the two women is betrothed to me. That means that in fact each and every one of the two women is betrothed to me in a faint way. This is quantum superposition. The state of the betrothal right now is a combination of two states. One state is that Rachel is betrothed to me and Leah is my wife’s sister. The second state is that Leah is betrothed to me and Rachel is my wife’s sister. And the real state is state A plus state B. Then it follows that even according to Maimonides I am forbidden to have relations with either of them. Why? Because she is not possibly my wife’s sister—she is definitely my wife’s sister. And she is also definitely my wife at the same time. But from the standpoint of being my wife’s sister, I am forbidden to have relations with her, because after all she is also my wife’s sister. So I am forbidden to have relations with her. Therefore even according to Maimonides this is called betrothal not fit for intercourse. And this is a state of certainty, not a state of doubt. This is what you called a definite doubt? Yes. It is definitely the case that this one is doubtfully betrothed to me and that one is doubtfully betrothed to me. In contrast, when there is doubt who is definitely betrothed to me, that is a doubtful certainty. Okay? Really this is just wordplay, because it would be more accurate to say not “definite doubt” but “definite faint betrothal,” not “definite doubtful betrothal,” but never mind—it’s just to contrast it with “doubtful certainty,” so that’s the terminology used. In the yeshivot that’s what they call it. The point is that this is a definite state and not a doubtful state. My claim is that the case of one who buys wine from the Cutheans is the same thing. In the case of one who buys wine from the Cutheans, when Rashi says—according to Rashi—that according to the one who says there is no retroactive clarification, every pair of logs in the mixture has the legal effect of terumah on it, one might have said that this is a state of doubt. The legal effect of terumah applies to one pair of logs, but since I don’t know which, then because of the doubt I must refrain from drinking. Right? And then I said that if it is rabbinic terumah then I can be lenient despite the doubt, because in a rabbinic doubt we are lenient. But the way I am saying it now, it is not like that. All pairs of logs are terumah—but faint terumah. This is a definite doubt, not a doubtful certainty. Because I did not define one particular pair of logs. So why assume that there is some pair of logs that is the terumah and I just don’t know which one it is? Who does know which one it is? The Holy One, blessed be He? Nobody knows, because there is no retroactive clarification. So there are no actual two logs that are the terumah at all. So how does Rashi tell me that all of them are terumah? Because this is not doubt; it is certainty. Every pair of logs you take is definitely faint terumah. It is quantum superposition. Okay? And therefore even if it were rabbinic terumah, in my view according to Rashi it would still be forbidden to drink, because this is not a state of doubt; it is a state of certainty. And a definite rabbinic prohibition is also a prohibition; it is forbidden to drink. Is there room to say that what you’ve now taken and are drinking, at that very second, definitely leaves the possibility of being what you called earlier the terumah? If you ask that question, then I’ll get into it in just a few sentences, and I’ll say this. Actually, I’m getting there in a moment, okay? A short introduction. I mentioned quantum theory, right? In quantum theory—one second. I mentioned quantum theory, right? In quantum theory—one second. I’ll share the diagram here. This is what in quantum theory is called the two-slit experiment. Fine, think about this thing here on the right. See it? That thing is a source that sends particles. Fine? Or you know what, let’s start differently—let’s start with Young’s experiment. This is a light source, a flashlight. Okay? It sends rays in all directions. The two rays marked with the thick dashed lines are rays that pass through slits. Fine? There are two slits in the screen in front of this flashlight, and this here is a screen—sorry, a barrier, okay? A barrier, and it has two slits in it, one slit here and one slit here. Here stands photographic film. This is photographic film. What will the film show? It will show a peak here and a peak here. Right? Two spots. Yes. Now what will also happen is there will be interference patterns, because this is a wave, so there will also be peaks in the middle. Okay? If these were particles—think of electrons or little balls, that this flashlight is sending little balls—then what we would see is one point here and one point here. Right? Two balls. Good. Now it turns out that the picture obtained in experiments done with particles is like the picture that Young’s experiment showed with light. Fine? On the other hand, on the other hand, if I take a single ball—quiet. What’s happening here? Where is that noise coming from? Okay. The point is that if I were now sending a single particle, then obviously it ought to be either here or here, right? Either it passed through the upper slit or it passed through the lower slit. It turns out, no. It turns out that I get two images or two impacts, both here and here. And this basically means that from the standpoint of quantum theory the particle does not pass either here or here, but rather both here and here. A single particle. Or in other words, that particle is really a wave. That’s what they call it in popular language. But what does it mean to be a wave? To be a wave means that the state of the particle is the sum of two particle states. One particle state is the passing of the particle through this slit and not that slit—that is, one point here. The second state is the passing of the particle through that slit and not this one—that is, a point only here. The state of the particle when I look at it as a wave is the sum of the two states. That means it is not correct to say that the particle passed through both slits, but rather that something of the particle passed through this slit and something of the particle passed through that slit. Something probabilistic. Meaning, this is not a state in which the particle passed through both slits, but a sum of two states, where in each state the particle passed through one of the slits. That is a huge difference, but that is the more precise quantum description. This is exactly what happens here too. I claim that according to Rashi, it is not that every pair of logs, every possible pair, has the legal effect of terumah on it. No. Rather, the state of the whole mixture is the sum of many states. Each one of the states is built like this: these two logs are terumah and everything else is ordinary produce. That is state A. State B: those two logs are terumah and the rest is ordinary produce. State C: those two logs are terumah and the rest is ordinary produce. The general state is the sum of state A plus state B plus state C. That is not the same as saying that the legal effect of terumah applies to all the logs. Because in each of them there is really only a faint legal effect, because it is only one of the states of the terumah. No, of course each one of the states is not full terumah; it is only some fraction of terumah. Therefore it resembles the quantum description of compound states, or superposition. Here later we described—I sent you this book—this is about the logic of time. You can see here the picture of Schrödinger’s cat, yes, the illustration. There is poison here inside this container, and inside it there is some particle that either decays or does not decay. If it decays, the poison is released, and if it does not decay, then the poison is not released. Now all this is inside a closed box. If the particle is in quantum superposition, meaning it is in a state of decaying plus a state of not decaying, then the poison is in a state of having dispersed plus a state of not having dispersed. If it dispersed, then the cat is dead. If it did not disperse, then the cat is alive. That means that the state of the cat is a superposition of a dead cat plus a live cat. The dead cat is the black one and the live cat is the standing one; really the cat is in—now there aren’t two cats, there is only one. Therefore this is a nice description of the point, just as there is only one particle in the situation I described above. Here too there is only one cat. So what does it mean that there is a dead cat and a live cat? It is not two cats; rather, the state of the same cat itself is the sum of two states. One state is a live cat, the second state is a dead cat. One-half times state A plus one-half times state B—that is the state of the cat. It is a bit strange to grasp this through our ordinary lenses, but that is basically what quantum theory says. My claim is that the one who says there is no retroactive clarification according to Rashi’s view is really looking at this as quantum superposition. That is the description of the state. Now look at something nice. Udi asked earlier: why not, if we take one of the women or one of the two logs, then maybe it will become clear after the fact that those are the two logs of terumah? Why not? Or for example in the case of someone who betrothed one of two women—say I betrothed one of a man’s two daughters, yes? I go to the father, give him a perutah, and say: one of your two daughters is betrothed to me. Yes, the picture of betrothal not fit for intercourse. So we said that this is betrothal not fit for intercourse, therefore there is a superposition here. Either this one is betrothed to me and the other is my wife’s sister, or the other is betrothed to me and this one is my wife’s sister. Superposition. Ritva and several other medieval authorities (Rishonim) ask, in different formulations: why shouldn’t the father choose one of the women, with the agreement of the betrother, give him that one, and then it will become clear that this is the woman whom he betrothed? On the face of it, a strange question. After all, if you tell me there is no retroactive clarification, let’s discuss according to Rashi and according to Rashba. If according to Rashi, then there is doubt regarding the two women: perhaps this one is betrothed, perhaps that one is betrothed. How can I suddenly choose one and decide that she is the betrothed one? There is a real doubt here. According to Rashba, no one here is betrothed; there was no act of betrothal. How can I choose someone and make her the betrothed one? The only way to understand Ritva’s question is only if I learn like Rashi and understand that this is not doubt but quantum superposition. Because in a case of doubt, too, you cannot just choose one. What do you mean choose? There is doubt whether this is the one or not; you can’t decide by choosing—it’s a real doubt. But if I understand that no, this is quantum superposition—what do we know from quantum theory? Let’s return to the diagram. I didn’t bring it here in this book, but in another book of Talmudic logic we did describe it. Let’s return for a moment to the diagram of Young’s experiment. Here, this diagram. If I now place a detector here, near this slit, this detector tells me whether the particle passed here or not. Do you know what will happen? If I put a detector here and send a particle, then either I will get an image here or I will get an image here. I will not get an image in both places. The detector tells me whether the particle passed. If the detector beeps, that means the particle passed here, and then I will see an image here. If the detector doesn’t beep, then the particle did not pass here. If it didn’t pass here, then obviously it passed here. If it passed here, then here I’ll get an image. Meaning, putting a detector here changes the outcome of the experiment even though the detector touches nothing and does nothing; I am simply checking where the particle passed. As long as you didn’t check. As long as I didn’t check where the particle passed, it passes through both slits together. But if I checked where it passed, then the detector causes the particle to stop being a wave and start being a particle. That is called quantum collapse. Meaning, it changes the state of the particle from a superposition, from a sum of two states, and chooses one of the two states: either the state in which the particle passed through the lower slit, or the state in which it passed through the upper slit. But it chooses one of the two states; it is no longer a superposition. The question Udi asked earlier is the same question, and that’s also what Ritva asks. If I betroth one of the two daughters of this man, then a state of superposition is created. Each of the two daughters is betrothed; this is a definite doubt. I definitely have that this one is faintly betrothed to me, and that one is faintly betrothed to me. Now I say: okay, let’s make a measurement. Let’s put in a detector. What does that mean? The father will take one of them and agree with me that this will be the woman to whom the betrothal took effect. Ritva asks: why won’t that work? What’s the problem? There is quantum collapse here. Once you created a state of superposition, if I measure, there is collapse. Of course, it’s not that Ritva understood quantum theory, but his logic happened to fit the logic that we see in quantum theory. He says: if there is basically a jumping between two states here, why can’t I choose one of them and then it will become clear retroactively that this was the correct one from the outset? Because after all, what you’re telling me is not that both of them are betrothed, but that this is a sum of two states, in each of which only one is betrothed. Fine—so if these are two optional states, like possible worlds, then I will choose one of the two optional states, and that will be the state; it will become clear retroactively that from the very beginning this was the one betrothed to me. That is Ritva’s question. By the way, Ritva also says as Jewish law that this would apparently indeed be the case, except that there is some technical problem that prevents doing it, for technical reasons. But in principle it really could work. And this is further evidence that he sees the state of betrothal not fit for intercourse as quantum superposition. What happens in questions of retroactive clarification? In questions of retroactive clarification this apparently is not possible. Why? Think, for example, about someone who writes the bill of divorce in the name of whichever one will go out first through the doorway. Let’s say there is no retroactive clarification. If there is no retroactive clarification, then there is really not one specific woman for whose sake the bill of divorce was written, and therefore we are in a state of superposition. Either the bill of divorce was written for this one, or it was written for that one. Okay? Now what are we going to do? If I choose one, what relevance does my choice have? Did she go out first through the doorway or not? After all, I made it depend on whichever one goes out first through the doorway. I can’t now choose some other woman. Therefore that is not relevant. Unless you say perhaps the going out through the doorway itself will do the selecting. But that is precisely the question of whether there is or is not retroactive clarification. According to the one who says there is no retroactive clarification, it is not possible. Only if I myself could select then perhaps it would be possible—but selection is possible in the case of betrothal not fit for intercourse, not here. Because in betrothal not fit for intercourse I did not make it depend on anyone’s intention. I said one of the two of them; I don’t care which. So someone can come and say: okay, then let’s agree now that this one will be the one. But here I did make it depend on something—I made it depend on the one who goes out first through the doorway. I can’t now just come and choose one of them however I feel like it. And ordinary selection is impossible according to the one who says there is no retroactive clarification, so it doesn’t work. Now I just want to finish with one more thing, get one more point in: the relation between a condition and retroactive clarification. I won’t have time to do it in great detail, but still. There is a chapter in the book about the difference between a condition and retroactive clarification. So Rashi explains the difference between condition and retroactive clarification in a certain way that is very forced, but Nachmanides explains it differently. And with this I want to finish. Nachmanides says as follows: “And this is the principle that I say regarding retroactive clarification. Anything whose condition is in the act—that he made the condition depend on one thing and one act—even if he made the condition depend on the act of others, it is valid. For example, the bill of divorce of a deathly ill man, according to the opinion that she is divorced retroactively; and likewise one who writes a bill of divorce in the name of so-and-so his wife, if she goes out first through the doorway before her fellows, and if not then it shall not be a bill of divorce—for if the condition is fulfilled, this is a bill of divorce.” Notice what he says here: this is not retroactive clarification, this is a condition. There are two women here, fine? What was the case of retroactive clarification? The case of retroactive clarification was: whichever one goes out first through the doorway, for her sake write the bill of divorce. That is the case of retroactive clarification. Nachmanides says: let’s take another picture. I say: write the bill of divorce for Rachel, on condition that she be the one who goes out first through the doorway, and if not, then the bill of divorce was not written for her sake. That is a condition, not retroactive clarification. Nachmanides says: according to all opinions, this works. Retroactive clarification depends on the question whether there is or is not retroactive clarification. This works according to all opinions. Now I will take Nachmanides one step further. Now I will construct the mechanism of retroactive clarification using two conditions. Fine? I now write two bills of divorce. One bill of divorce in Rachel’s name, on condition that she goes out first through the doorway. The second bill of divorce in Leah’s name, on condition that she goes out first through the doorway. Okay? Now the husband comes and gives Rachel’s bill of divorce to Rachel and Leah’s bill of divorce to Leah. Fine? The next morning it becomes clear that Rachel is the one who goes out first through the doorway. Is there a valid bill of divorce here? The answer is yes, according to all opinions, even according to the one who says there is no retroactive clarification. Why? Because here I simply made two bills of divorce, each one conditional. This is not retroactive clarification. Although I implemented—think of it in terms of electrical circuits—I implemented the result of retroactive clarification by means of conditional circuits. Meaning I created the same result. I basically created a situation in which I divorced whichever one would go out first through the doorway tomorrow, but I built it in such a way that it is two mechanisms of condition and not one mechanism of retroactive clarification. This works according to all opinions. Even according to the one who says there is no retroactive clarification it works, because here there are two bills of divorce, and each bill of divorce is directed to one woman, not to two. It depends on a condition—either it will be a bill of divorce for her or it won’t be a bill of divorce for her. A case of retroactive clarification is where I have one bill of divorce directed to one of two women, and depending on what happens it is directed either to her or to her. That depends on the dispute whether there is or isn’t retroactive clarification, says Nachmanides. But if I write one bill of divorce for one woman, only I make it depend by condition on whether the act takes effect or not, everyone agrees that this works. And I write another bill of divorce for another woman, and I also make that one depend on a condition. That is no problem; there is no dispute at all about that. These are two conditions, two bills of divorce with conditions, and a bill of divorce with a condition works according to all opinions. No one ever disputed that. The mechanism of condition is agreed upon by all the sages. There is dispute about retroactive clarification, not about condition. Nachmanides says: that is the difference between retroactive clarification and condition. The difference is whether you perform one act and try to select one of two women, or one pair of logs, or one direction of the two eruvs, east or west—that is retroactive clarification. And that depends on the question whether there is or isn’t retroactive clarification. But if you perform an act on one object, only you make it conditional whether the act will take effect or not—that everyone agrees works. What is the difference? The difference is that in retroactive clarification, as I said earlier, this is marking. Condition is causation. In retroactive clarification I mark one out of several objects, and the one act I performed, I performed on that marked object. That is a mechanism entirely different from condition. Condition is an act performed unequivocally now on a well-defined object. It only depends on a future condition whether it will take effect or not. It is not there to select or mark one out of several objects to which the act will apply. The object to which the act will apply is completely clear. The question that depends on the condition is whether the act will take effect or not take effect, not who the object is to which the act will take effect. That is retroactive clarification. But if the object is well defined and I only need to make a condition whether the act will take effect upon it or not, that is a condition. And that is agreed upon by all opinions. That is the difference between retroactive clarification and condition. Even though it is very confusing, and even though one can implement the idea of retroactive clarification through two conditions on two bills of divorce, or terumah separations on whatever two logs you want—according to Nachmanides one can do that, and it will take effect according to all opinions. But if you didn’t do it through implementations of several conditions, but rather through a mechanism of retroactive clarification, then it won’t work. Now Nachmanides—and with this I’ll finish—adds another interesting remark. Come, he says the same thing about the eruv. One who says: if a sage comes to the east, my eruv is to the east, and if not—not that the eruv should be to the west, but if not, my eruv is void. And the western eruv too—he also puts it there and says conditionally: if the sage comes to the west, it takes effect; if not, it is void. This will work. Notice that here too there are already two eruvs, both in condition and in retroactive clarification. It is literally the same thing, and yet the mechanism of condition works and the mechanism of retroactive clarification does not work. That sharpens the difference very much. Now look what he does. “But one who makes it depend on the will of others or on his own will, even though he did not make it conditional on two things, we do not say that when he wants, the matter becomes clarified and takes effect from the outset, except according to the opinion that there is retroactive clarification. And this is why in our passage they bring the case ‘on condition that father wants,’ as I explained.” Remember that at the end of the previous lesson we saw that the Talmud brings a man who gives betrothal to a woman, gives a perutah to a woman, and betroths her on condition that father agrees. Fine? Meaning I make it conditional on my father agreeing to this betrothal. Okay. Seemingly this is a condition: if father wants it, it is betrothal; if father doesn’t want it, it is not betrothal. According to Nachmanides’ definition above, this is really a condition and not retroactive clarification, right? So why does the Talmud tie it to the sugya of retroactive clarification? Nachmanides says as follows: a condition of this kind, where you make it depend on the will of a person—others or yourself—even though he did not make it conditional on two things, we do not say that when he wants, the matter is clarified and takes effect from the outset, except according to the opinion that there is retroactive clarification. Why, if it isn’t clarified, when is it clarified? I didn’t understand—what does “clarified when” mean? “The matter is clarified and takes effect from the outset.” Retroactively? Yes. For example, if I give betrothal to a woman on condition that father agrees, and if father does not agree it is not betrothal. Seemingly this is not retroactive clarification, right? It is a condition. There are no two women here such that I decide which of them to betroth. There is one woman; I gave her betrothal on condition that father agrees. What does this have to do with the dispute of retroactive clarification? But the Talmud does in fact connect it to the dispute of retroactive clarification. So that does not fit Nachmanides’ definition above, because Nachmanides defined a case in which there is only one defined object as a case of condition, not retroactive clarification. So Nachmanides says this: here the future event is an event of choice. It depends on the will of others or on his own will. What does that mean? That the information does not exist before the event happens, right? Because it depends on a person’s free choice. That is the third level in our hierarchy, right? Nachmanides says: if you make such a condition, where you make it depend on someone’s will, then it depends on the dispute whether there is or isn’t retroactive clarification. Only a condition such as “if rain falls” is a condition. But a condition such as “if father wants,” or “if I want,” or a condition that someone else does something depending on choice—that depends on the dispute whether there is or isn’t retroactive clarification. Why? It takes me right back to exactly what I said earlier, because now we have finished covering the four levels in the hierarchy I described before. The first level is information that exists now: a son was born to me and I don’t know who he is. The second thing is a future event that is not an event of choice. That is the mechanism of retroactive clarification. The third thing is a future event that depends on choice; about that I had not yet said anything. Nachmanides says that even if it is about a single object, it will still depend on the question whether there is or isn’t retroactive clarification—that third event. The fourth event is that the future event is the cause of the present state—that is a condition. That is agreed upon by everyone. So now we have a characterization for each of these four levels that we saw in the philosophical introduction. Yes, in fact each of them corresponds to a legal category, a halakhic category, of its own. The first level is just simple disclosure of a fact retroactively—that is nothing; it depends neither on retroactive clarification nor on condition, it is simple. The second level depends on the dispute whether there is or isn’t retroactive clarification. The third level, something that depends on will, depends on the dispute whether there is or isn’t retroactive clarification even if it is a single object, not only if it is two objects. And the fourth level is condition—that is backward causality in time. And the latter part is “if I die,” ‘this is your bill of divorce from today’—that’s condition and not retroactive clarification? Right, seemingly. Nachmanides says, why not? Because the Talmud brings it in the context of retroactive clarification. After all, “this is your bill of divorce if I die,” the Talmud explains there that it means a moment before my death, not from now. If I remember correctly, there Rabbi Yosei says she is divorced and not divorced. Look at Rashi there and see Nachmanides; Nachmanides explains there that what the Talmud is discussing in tractate Gittin is a situation where she is divorced a moment before his death. Nachmanides says: that is exactly retroactive clarification. Why is it retroactive clarification? Because you are selecting one moment out of many moments at which the bill of divorce takes effect. Therefore that is exactly not condition but retroactive clarification, precisely by Nachmanides’ definition. All right? Okay. If there are any comments or questions, you can raise them now. Also comments and takeaways regarding this series. So if someone wants to, now is the time. First of all, thank you—and when is the next class? The next class is next year. We finished the semester. Also the next track. Yes. So in short, if anyone has any further comment, send it to me. All right? Have a pleasant break, good luck. Have a pleasant break, thank you very much, thank you very much, thank you very much, goodbye. It was very interesting.