"And Do Not Stray After Your Eyes" – On Superficiality in the Perception of Facts (Column 75)

With God's help

Parashat Shelach opens with the sending of the spies "to scout the land". The verb to scout / to spy out recurs quite a bit in the passage, and one gets the impression that their main problem was that they functioned as tourists; that is, they were impressed by the immediate appearance of things and did not investigate their meaning deeply enough. At the end of the passage appears the section of tzitzit, containing the command "And do not stray after your hearts and after your eyes", which is ostensibly the correction for the sin of the spies. The verse instructs us not to be taken captive by visual appearance or by the inclinations of the heart. It is worth investing a bit more thought and asking whether what meets the eye truly reflects the truth, or whether it conceals behind it something a bit different.

The sin of the spies was that they scouted the land; that is, they brought their own interpretation to the facts as though those interpretations were the facts themselves. The spies repeatedly return and report that it is "a land that consumes its inhabitants" – a land that consumes its inhabitants. Rashi (Numbers 13:32) cites the rabbinic midrash:

“It consumes its inhabitants” — wherever we passed, we found them burying the dead, and the Holy One, blessed be He, did this for the good, in order to keep them occupied with their mourning so that they would not pay attention to these people.

They saw dead people and immediately interpreted this to mean that it was a land that consumes its inhabitants. But the truth is that God performed a miracle for them in order to help them, so that the inhabitants of the land would not pay attention to them.

On the one hand, what the eyes see is regarded as the strongest kind of evidence: "Hearing should not be greater than seeing." ("hearing should not be greater than seeing"). On the other hand, the eyes are a very superficial and very misleading instrument. They carry us away and convince us that if we saw something, then that must certainly be the truth. It is hard to cast doubt on eyewitness testimony. It is no less difficult to think again about the meaning of what we saw, and whether it really is what it appears to be. The Torah's command of "Do not stray after your eyes" apparently comes to correct the sin of the spies. It instructs us not to rush to draw conclusions from facts we have seen. At the very least, it is very important that we distinguish between the facts and the interpretation given to them.

I will begin with two examples that illustrate the point specifically in halakhic interpretation.

First example: the Second Passover

In the previous passage (Beha'alotekha), people who had been ritually impure and therefore could not offer the Passover sacrifice at its appointed time come and ask Moses for a second chance (Numbers 9:6-7):

And there were men who were impure through contact with a human corpse, and therefore could not offer the Passover sacrifice on that day; and they approached Moses and Aaron on that day. And those men said to him: We are impure through contact with a human corpse; why should we be deprived of offering the Lord's sacrifice at its appointed time among the children of Israel?

They ask to be given an opportunity to make up what they missed. This request itself already seems puzzling. Why did they not come with similar requests regarding Grace after Meals, redemption of a firstborn donkey, or Sabbath observance? Why did someone who was ill and had to violate the Sabbath not ask Moses for the possibility of an alternative Sabbath (say, on Wednesday)? Why does this happen specifically with regard to the Passover sacrifice?

Surprisingly enough, this request turns out to be entirely appropriate. First, Moses himself does not dismiss them outright, but forwards the request onward (ibid., 8):

And Moses said to them: Stand still, and I will hear what the Lord commands concerning you.

God too treats this very seriously, and even grants the request (ibid., 9-12):

And the Lord spoke to Moses, saying: Speak to the children of Israel, saying: If any man becomes impure through contact with a corpse, or is on a distant journey, whether among you or in your generations, he shall offer a Passover sacrifice to the Lord. In the second month, on the fourteenth day, at twilight, they shall offer it; they shall eat it with matzot and bitter herbs. They shall leave none of it until morning, and they shall not break any bone of it; according to all the statute of the Passover they shall offer it.

Here the section of the Second Passover is introduced. One who was impure or on a distant journey and therefore could not offer the Passover sacrifice at its appointed time may make it up on the Second Passover (14 Iyar) and offer a substitute sacrifice there.

The section concludes with the punishment of being cut off for one who did not offer the Passover (ibid., 13-14), and with the fact that the obligation rests on every individual among Israel (the convert and the native-born alike):

But the man who is pure and was not on a journey, and yet refrains from offering the Passover sacrifice, that soul shall be cut off from his people, for he did not offer the Lord's offering at its appointed time; that man shall bear his sin. And if a convert sojourns among you and offers a Passover sacrifice to the Lord, according to the statute of the Passover and according to its ordinance, so shall he do; one statute shall apply to you, both to the convert and to the native of the land.

Is the Second Passover a make-up for the first?

In the Talmud (Pesachim 93) a dispute among the tannaim is cited regarding the nature of the Second Passover:

For it was taught in a baraita: A convert who converted between the two Passovers, and likewise a minor who came of age between the two Passovers, is obligated to observe the second Passover; these are the words of Rabbi. Rabbi Natan says: Whoever was subject to the first is subject to the second; whoever was not subject to the first is not subject to the second. About what do they disagree? Rabbi holds that the second is a festival in its own right, while Rabbi Natan holds that the second is a make-up for the first; and one who was not obligated in the first cannot rectify it.

Rabbi Natan maintains that the Second Passover is a make-up for the first; that is, one who did not offer the first makes it up by offering the second. But Rabbi holds that the second is an independent festival in its own right. The implication concerns a convert who converted after the first Passover, or a minor who came of age after the first Passover. According to Rabbi Natan, who sees the second as a make-up for the first, these two are exempt from the Second Passover. They were not obligated in the first, and therefore there is no reason for them to bring the second. But according to Rabbi, the Second Passover is an independent obligation and not a make-up for the first, and therefore these two are obligated to bring the Second Passover. True, one who brought the first Passover is exempt from the second, but in Rabbi's view this is a festival in its own right, and one who did not bring the first, even if he was not obligated at all at the time, is not exempt from the second.

Even more surprisingly, Jewish law rules in accordance with Rabbi, that the Second Passover is a festival in its own right. For example, Maimonides writes in Laws of the Passover Offering 5:7:

A convert who converted between the first Passover and the second Passover, and likewise a minor who came of age between the two Passovers, is obligated to observe the second Passover; but if it was slaughtered on his behalf at the first, he is exempt.[1]

How are we to understand Rabbi's view? The verses present the Second Passover very clearly as a make-up for the first. One who could not bring the first is given an opportunity to make it up with the second. How does Rabbi arrive at the conception that this is an independent obligation? And what explains the fact that Rabbi too agrees that one who did bring the first Passover is exempt from the second? If it is a festival in its own right, everyone should be obligated in it. How does his view fit the biblical facts?

A logical solution

Let us look at this passage in a coldly logical way. Two facts emerge from the biblical text: 1. There is an obligation to bring the first Passover. 2. One who did not bring the first Passover brings the second.

At first glance, one can propose two similar but not identical interpretations of these two facts:

• The second is a make-up for the first, that is, one who did not bring the first becomes obligated in the second.
• The second is an independent obligation, but one who brought the first is exempt from it.

Both of these conceptions/interpretations fit the two biblical facts above. Rabbi Natan chose the first, and Rabbi chose the second. For Rabbi, failure to bring the first is not the cause of the obligation of the second; on the contrary: the second is an independent obligation, but bringing the first exempts one from the second. The practical halakhic difference between these conceptions is the case of a minor or a convert who entered the sphere of obligation between the two Passovers.

Interpretation A assumes that the first Passover is a regular halakhic obligation, and the second is an opportunity to fulfill it for one who could not do so. Interpretation B, by contrast, assumes that these two obligations bring us to some goal. Therefore, one who did the first is exempt from the second, but one who did not do the first, even if he was not obligated, must bring the second.

The purpose of these two sacrifices is apparently incorporation into the community. The Passover sacrifice is one that each individual brings, but there are several indications that it has laws of a communal sacrifice (for example, a ritually impure community may bring it). The explanation is that the Passover sacrifice fuses individuals into a community.[2] Therefore the section ends by stating that one who did not bring the sacrifice incurs being cut off. He is cut off from the Jewish people. The next verse teaches that everyone must bring it, convert and native-born alike, since they too (and perhaps especially they) must undergo this fusion and be included in the community.

Now it is clear that if there is a minor or convert who came under obligation after 14 Nisan, then so long as by 14 Iyar they are already obligated, they must be included in the community through the Second Passover. But one who already offered the first is exempt from the second because he has already been included in the community. This is probably also the explanation for why, specifically with this commandment, those who were impure come and ask for a second chance. They understand that they have not merely missed a commandment, as in the case of Grace after Meals or Sabbath observance; rather, they are not at present included in the community. Therefore they ask that their share not be diminished and that they too be able to be included in it. There is an important result that they have missed, and they want a way to make it up.

Preliminary analysis: Leibniz's analogy of the clocks

At a superficial glance it seems clear that the Second Passover is a make-up (a completion) for the first, that is, that there is a causal relation between them (failure to bring the first is the reason one becomes obligated in the second). But cold logical analysis brings us to the conclusion that there are other possibilities (in the Talmud in Pesachim there is a third view, which I have not presented here): namely, that both are means to some shared end. The biblical correlation, that only one who did not bring the first is obligated in the second, does not necessarily indicate a causal connection. There are correlations that have another explanation.

Leibniz, in his discussion of the relation between body and soul, offers an analogy relevant to this point. Suppose we see two clocks that constantly show exactly the same time. There is a correlation between the facts we observe. Does that mean that one clock is the cause of the other, or vice versa? In this case the explanation is not causal. It is a correlation not based on causality. Here the synchronization between the events is created by a third factor (the clockmaker or clockmakers), and not because of a causal relation between the events.

Cum hoc ergo propter hoc

Those who work in statistics often joke about such cognitive failures, which hastily translate correlation into causal relations. This fallacy is called in Latin cum hoc ergo propter hoc. In many cases we give an interpretation to the facts we observed, but fail to notice that these are not pure facts but facts together with an interpretation. We saw that only one who did not bring the first Passover brings the second Passover, and we immediately jumped to the interpretation that failure to bring the first Passover is the cause of the obligation of the second Passover. But it is not so.

Thus, for example, some might conclude that it is forbidden to diet, because only overweight people diet. The correlation between overweight people and dieting is interpreted as a causal relation: diet -> fatness. In this case there is a causal relation, but in the opposite direction. I once saw a letter from a professor at the Technion who wrote that it is very important to invest in higher education because countries that invest in higher education have a higher GDP. Again there is a fallacy here, for an interpretation no less plausible is that countries with a high GDP have money to invest in higher education.

One must understand that the direction of the correlation is critical. According to the interpretation suggested here, there is no reason to avoid dieting in order not to become fat, and no reason to invest in higher education in order to increase GDP. These are not mere sophistries. These interpretations have very important consequences. Quite a few medical studies point to a correlation between variables, but correlation as such does not tell us very much. If one takes two groups, one composed of coffee drinkers and the other not, and checks the percentage of cancer patients in these two groups, and suppose we discover that among coffee drinkers the percentage of patients is significantly higher, does that mean coffee is carcinogenic? Not necessarily. It may be that cancer patients have a tendency to drink coffee. The implication is that such a study does not necessarily present a reason to refrain from drinking coffee. All of these are failures in the transition from factual correlation to causal interpretation. Sometimes there is no causal connection at all, and sometimes the connection runs in the opposite direction (as we saw above: bringing the first Passover exempts from the second, not that failure to bring it is the cause of the obligation of the second).

Second example: the tekhelet and the white in tzitzit

The second example deals specifically with the opposite case, where ostensibly there is no connection between things, but interpretation reveals that there is in fact a connection between them. At the end of Parashat Shelach appears the section of tzitzit, in which the command of "And do not stray" is written:

And the Lord said to Moses, saying: Speak to the children of Israel, and tell them that they shall make for themselves fringes on the corners of their garments throughout their generations, and they shall place upon the fringe of each corner a thread of sky-blue wool. And it shall be for you as fringes, and you shall see it and remember all the commandments of the Lord and perform them, and you shall not stray after your hearts and after your eyes, after which you go astray. So that you may remember and perform all My commandments, and be holy to your God. I am the Lord your God, who brought you out of the land of Egypt to be your God; I am the Lord your God.

The Torah instructs us to place tekhelet and white threads on the corners of our garment, and this will be tzitzit for us. This raises the question whether we are dealing with one commandment or two. Are the tekhelet and the white two different commandments, or are they two details within one commandment?

Components that do not prevent one another

Seemingly, this can be resolved from the Mishnah in Menachot 38a, which states:

The sky-blue thread does not prevent the white from fulfilling the commandment, and the white does not prevent the sky-blue thread; the hand-tefillin does not prevent the head-tefillin, and the head-tefillin does not prevent the hand-tefillin.

There are two parallel determinations here, regarding the tekhelet and the white in tzitzit and regarding the arm-tefillin and the head-tefillin. In both cases we are dealing with two details that do not prevent one another, that is, failure to do one does not interfere with doing the other. Seemingly, the conclusion that suggests itself is that these are two different commandments.

Yet Maimonides counts the commandment of tzitzit as one commandment (positive commandment 14) that has two details (the tekhelet and the white), whereas tefillin he counts as two different commandments (positive commandments 12-13). He addresses the matter in positive commandment 14, where he writes:

The fourteenth commandment is that He commanded us to make tzitzit, as He said, may He be exalted, at the end of Parashat Shelach: “And they shall make for themselves fringes,” etc., “and they shall place upon the fringe of each corner a thread of sky-blue wool.” And you should not count this as two commandments, even though the principle accepted by us is that the sky-blue thread does not prevent the white, and the white does not prevent the sky-blue thread, for it is stated in the Sifrei: One might think that these are two commandments, the commandment of the sky-blue thread and the commandment of the white thread; therefore Scripture says, “And it shall be for you as tzitzit” — it is one commandment and not two commandments. Women are not obligated in this, as was explained at the beginning of tractate Kiddushin, and the general laws of this commandment have already been explained in the fourth chapter of tractate Menachot.

He cites that the Sifrei derives from the wording of the verse here, "And it shall be for you as tzitzit", that this is one commandment.

So again we have here two cases, in each of which there are two details that do not prevent one another. Moreover, the Mishnah presents them in parallel to one another. Seemingly, the conclusion that suggests itself is that the details are independent, that these are two pairs of commandments. But Maimonides draws a distinction between tzitzit and tefillin.

The more detailed explanation appears in Principle 11, where Maimonides establishes that if the details prevent one another, then they are certainly parts of one commandment. But when the details do not prevent one another, the situation is not simple. There Maimonides distinguishes between different cases in which one detail does not prevent another. Sometimes it is one commandment and sometimes these are two different commandments. There are cases in which the two details create a single whole, and nevertheless one does not prevent the other (as in tzitzit), and there are cases in which these really are two details that do not create a whole, that is, they are independent (as in tefillin).

In my article in Akdamot I explained that in fact we are dealing with two different meanings of the fact that one detail "does not prevent" another. Let me preface this by saying that many people misunderstand the meaning of the term prevention. For example, to the best of my understanding, beautification of a commandment, although it does not prevent fulfillment of the commandment itself, is a full obligation and not merely a voluntary matter. Thus, someone who built an unbeautified sukkah has indeed fulfilled the obligation of the commandment of sukkah, but has neglected the commandment of beautification ("This is my God, and I will glorify Him.").[3] By the same token, if tekhelet does not prevent the white, that does not necessarily mean that placing a tekhelet thread is voluntary (that is, that this is a merely optional commandment, such that if you did it you receive reward and if not, nothing happened). It is entirely possible that tekhelet is a fully obligatory commandment in every respect, and one who did not place tekhelet in the tzitzit has neglected the positive commandment of tekhelet. Yet if he places white threads, he has fulfilled the commandment of the white, since the absence of tekhelet does not interfere with the fulfillment of the white.

Now let us return and ask ourselves what happens if I placed only white threads in my garment, without tekhelet. One might have thought that such tzitzit are valid in the sense that one fulfills through them the commandment of the white, but clearly the commandment of tekhelet has not been fulfilled. Alternatively, one might also think that with such tzitzit one has fulfilled the commandment of tzitzit, but done so in an incomplete way. The first interpretation sees the tekhelet and the white as two independent details, whereas according to the second these are two details that together create a single whole, except that this whole appears in partial form even when only one of the details is fulfilled without the other. These are two meanings of the claim that tekhelet does not prevent the white.[4] In the first sense the two details are two different commandments (this is the case with tefillin), whereas in the second they are two details of one commandment (this is the case with tzitzit). Maimonides understands that this is the case in tzitzit from the midrash he cited, which in fact derived it from the wording of the verse, that after instructing us to take white and tekhelet it states "And it shall be for you as tzitzit". That is, these two details together constitute a whole called tzitzit.[5]

Back to correlation and causality

Many have wondered about Maimonides' words and raised difficulties against them. They assumed that the appearance of the commandments of tzitzit and tefillin in the same Mishnah and in the same formulation indicates that the relation between the details in the two cases is identical. But Maimonides teaches us that it is not. What we see on the factual and superficial plane is that there is no connection between the details. But a deeper look reveals that this is not so. The halakhic connection (or lack of connection) between the details does not always reflect the deep structure they create. Once again we encounter the meaning of "And do not stray after your hearts and after your eyes" in the sphere of halakhic interpretation.

A note on causality

This analysis is what led David Hume to cast doubt on causality. He showed that the determination that there is a causal relation between two events is based not on observation but on interpretation alone. When I see a log lying in fire and always burning, I give this the interpretation that the fire is the cause of the burning. But what I see with my eyes is only the correlation and not the causal relation. I see the juxtaposition of the events of being in the fire and burning. The question whether one is the cause of the other is a matter of my interpretation. There is no empirical way to ground that interpretation.

David Hume, as a thoroughgoing empiricist, gave up that metaphysical interpretation and redefined the causal relation as mere temporal succession. When we say that being in the fire (event A) is the cause of the burning (event B), this does not mean that there is a relation of production between the events, but only that event B always appears after event A. Ostensibly he is careful to avoid the fallacy we have discussed and clings to the facts without interpretation.

This is the place to note that sometimes this is excessive caution. It is indeed important to distinguish between the facts and their interpretation, but on the other hand it is not correct to assume that only the facts are true and that interpretation is necessarily something subjective and mistaken. That assumption too is a kind of fallacy. Clinging to facts without a willingness to accept interpretation is of course not necessary. More than that: sometimes precisely the clinging to the dry facts and the rejection of interpretations is itself the very act of straying after the eyes. Hume the empiricist clung to his eyes and was unwilling to grant legitimacy to interpretation beyond them. A person can (and in my opinion should) adopt interpretations that seem reasonable to him, so long as he is careful to distinguish between the facts and the interpretation he gives them. This subject is treated in my books Shtei Agalot VeKadur Pore'ach and Emet Velo Yatziv.

If we return to the matter of "And do not stray after your hearts and after your eyes", the sages derive from here a prohibition on engaging in heresy and arguments of unbelief. According to my suggestion here, the meaning is somewhat different. One can, and perhaps should, engage with arguments of all kinds, but one must be careful not to be misled by what appears before the eyes. Sometimes such arguments present facts to us and we tend to be persuaded immediately (Heresy is different, because it exerts a pull., "for heresy exerts a pull"), whereas in fact we are dealing with facts together with an interpretation. Thus evolution is presented as a refutation of faith, and the findings of neuroscience are presented as though they contain a contradiction to our free will (evidence for determinism). I have dealt with these subjects as well in my books, Elohim Mesachek BeKubiyot and Mada'ei HaHerut.

[1] The latter clause of his words is puzzling, and many have already dealt with it; we will not enter into it here.

[2] This fusion is carried out through families and registered groups. Individuals organize into families, and these are fused into a community. This is the rule of "for those registered for it" regarding the Passover sacrifice.

[3] I am not entering here into the question of the status of this commandment (whether it is Torah-level) and why it was not counted.

[4] Incidentally, according to both of these interpretations one can say that there is here a neglect of the commandment of tekhelet (or a partial neglect of the complete commandment of tzitzit). I will not enter into that here.

[5] Elsewhere I argued that the wording of Scripture, "And it shall be for you as tzitzit", teaches that the concept of "tzitzit" existed even before the Torah's command, and that the Torah merely commands us how we are to make our tzitzit. In the terminology accepted in analytic philosophy, this is a directive commandment rather than a constitutive one. Here we see another interpretive possibility for that verse.