On Armchair Research and “Computational Archaeology” (Column 341)
Some time ago someone sent me an article from YNET with the enthusiastic headline: “Traces of the measure ‘tefach’ were found in archaeological findings.” The article reports a fascinating result: the size of the tefach was confirmed by archaeological means. The study also supports the (captivating) hypothesis that jar production in that period (the Kingdoms of Judah and Israel, in the 10th–7th centuries BCE) was carried out exclusively by male potters.
The research was conducted by scholars from the Weizmann Institute and the Hebrew University in collaboration with the Israel Antiquities Authority. It mentions institutions with grand names such as “The IAA Laboratory for Digital Documentation and Research in Archaeology,” or the Hebrew University’s “Laboratory for Computational Archaeology.” At first glance this all sounded truly intriguing, so I went to read. At last, I thought to myself, we’ll be able to settle the dispute of the Chazon Ish (and the Noda BiYehuda) versus R. Chaim Naeh; and if we examine the implications for measures of volume such as the “kezayit,” perhaps we even have a chance to get through the upcoming Seder night alive (i.e., without choking on the matzah).
Description of the findings and their interpretation
The researchers relied on three groups of storage and trade jars produced in different places in the Land of Israel. Three hundred jars with an average capacity of 40 liters were scanned in 3D. The study measured shape and size characteristics of the jars—such as volume, height, and maximum diameter—and compared these among the groups. The measurements indicated a lack of uniformity in the sizes measured within each group, but there was one exception: a single dimension that was precisely shared by all the jars—the inner mouth diameter of the jar’s neck. The measured diameter averaged 88–89 mm, which lies in the middle of the commonly accepted range for the “tefach”—a width measure of four fingers—an ancient unit mentioned in the Bible. One hypothesis is that the jar mouths were made in a uniform size to create an opening small enough for effective sealing—important for storage and transport—yet still large enough for easier filling and pouring.
[As part of my armchair research, seated as a researcher in the a priori laboratory for hypothesis-raising in archaeology, I wondered whether the explanation is more prosaic: perhaps there was a single monopolistic producer of jar lids who made only one lid size, and all the manufacturers conformed to that lid size.]
The researchers linked the mouth size to the process of making the jars, in which potters needed to insert a hand inside, or to a size that allows inserting a hand to clean the jars from within after use, or to prevent the entry of impurity (via an opening of a tefach), and so forth. [According to my hypothesis above, this need not be the case, of course. M.A.] In the researchers’ words, “A width that meets all these requirements is the size of a tefach, which is easy for different potters to apply. It would have been natural for ancient potters to adopt the size of the tefach, since it was a widely used unit of length in antiquity, mentioned in Assyrian and Egyptian sources as well as in the Book of the Covenant.” [It’s unclear to me whether they adopted this uniform size—i.e., set a standard unit of length that was transferred among all manufacturers and used in production—or whether each craftsman used his own hands, in which case all the hands of that era would have been of uniform size.]
The researchers buttressed the link between the tefach and the jar-neck diameters by comparing the distribution of jar-mouth sizes with measurements of male and female hand breadths from U.S. Army anthropometric databases. I [M.A.] hope they used measurements from the U.S. Army of that era (i.e., from the appropriate Native American tribe), otherwise we have a worrying anachronism. Oops—turns out they didn’t, since they report assuming that physical hand breadth hasn’t changed over the last three millennia. In any case, the results showed a match between the distribution of jar-mouth sizes and the hand-breadth distribution of men, but not of women.
And the conclusion: these data strengthen the claim that in this case we can clearly identify the use of the ancient tefach, preserved in the jar-manufacturing process, with an average size of 88–89 mm. Moreover, the test supports the hypothesis that the production of these vessels in the period in question was entrusted to male, not female, potters. So much for the study’s conclusions.
Critique from the A Priori Laboratory for Armchair Research and Hypothesis-Raising
The researchers, as noted, assume that finger breadths haven’t changed over three thousand years, measure today’s finger-breadth distribution, and compare it to the historical jar-mouth widths. From this they infer the tefach’s size. And I wonder about the logic of this argument. Seemingly, if we measure finger breadths today and assume the breadth hasn’t changed, we directly obtain the size of the tefach. Why run a field study? The two premises the researchers adopt—without any additional empirical information—by themselves yield, through a simple logical argument, their conclusion. So why, for heaven’s sake, did they need to do “computational archaeology,” use the digital documentation institute’s scans, and analyze the results for this? They could have stayed in their armchairs, posited those two assumptions, and moved straight to typing the paper and sending it to the archaeological journal BASOR.
I’ll go further. My learned predecessors in the Laboratory for A Priori Hypothesis-Raising conducted precisely such an assessment centuries ago. I refer to the halakhic decisors (poskim), who generally assume the measure hasn’t changed, and therefore measure it in their own days and extrapolate to the biblical and Talmudic tefach. It’s a pity the researchers at the computational archaeology lab missed the a priori armchair experiments conducted by Prof. Yechezkel Landau, Prof. Avraham Yeshayahu Karelitz, and Prof. Chaim Naeh, who were centuries—at least decades—ahead of the science of their time. “Turn it and turn it, for everything is in it,” and blessed is He who chose them and their teachings, “for it is your wisdom and understanding in the sight of the nations” (as it says: “and lean not on your own understanding”).
After further thought, a few more possibilities occurred to me. Perhaps their intent was really a study in physical anthropology rather than historical archaeology. That is, maybe the researchers merely wished to empirically confirm the assumption that finger thickness hasn’t changed in three thousand years; for that purpose they assumed the neck diameters reflect a tefach, and then compared them to current U.S. Army data. Here there is an explanation for getting up from the armchair, since such a conclusion does require fieldwork and actual measurement of those diameters. But even this armchair hypothesis doesn’t hold up, since it’s unclear, on this reading, whence their conclusion that the potters were men. Perhaps the jar-makers back then were women, only female finger thickness has changed over the generations? Alternatively, perhaps it was five fingers of men rather than four, and their finger thickness (and maybe women’s too) has increased?
Then I thought perhaps the study’s goal was social-historical: to understand why jar necks were made precisely at that width. Once the researchers discovered that the neck width is a Talmudic/Biblical tefach, the reasons for this captivating riddle became clear: the need to insert a hand to form the jar and to clean it, and also the trade-off between transport (favoring a small opening) and easy pouring (favoring a larger one).[1] I am not an archaeologist, and besides, I too enjoy the occasional bit of silliness, so I will refrain here from commenting on the far-reaching importance of this conclusion.[2]
Don’t think I’m merely a ceremonial head of the famous laboratory I described—this isn’t mere nepotism. I have rich, proven experience in archaeological digs, since as a mischievous youth I joined my Bnei Akiva tribe for an archaeological summer camp where we excavated at Herodion (yes, you hikers there, know that you tread trails I myself carved with the sweat of my brow). I remember that when I was a lad, I cursed the pint-sized Bar Kokhba fighters who lived and fought in tunnels a meter high. Again and again I asked why it was decreed upon me—a Jew eight cubits tall (by a man’s cubit), with a bed of iron—to live a week bent double in their Lilliputian burrows?! In any case, this finding independently supported the widespread hypothesis that the human body has indeed changed since then (height and size have marvelously increased). In light of this experience, I asked myself yet again what basis the researchers have for assuming finger thickness stayed the same (see more below).
Incidentally, Prof. Yechezkel Landau—yes, the same—writes a contrary a priori assumption in his novellae to Pesachim 116b, in these pearly words:
[…] If so, two measures for challah contradict one another, and both are a halakhah le-Moshe mi-Sinai: the measure of 43 eggs and a fifth is a halakhah le-Moshe mi-Sinai, and likewise the mikveh measure is a halakhah le-Moshe mi-Sinai. Necessarily it has changed in our time: either the thumbs have become larger and are bigger than the thumbs in the days of the Tannaim, or the eggs have become smaller and are, in our time, smaller than in the days of the Tannaim. And it is known that the generations decline, and it is impossible that our thumb is larger than the thumbs of the sages of the Talmud. Necessarily, the eggs in our time have diminished. QED.
He claims that the decline of the generations is expressed in a decrease in physical size; therefore our bodies cannot be larger than those of the ancients, and so on.
These groundbreaking a priori findings stand in contrast to the researchers’ hypothesis, but also to the empirical findings from my Herodion “study” above [and to reality as well. But there’s no need to reiterate here that we are dealing with qualitative, a priori armchair research whose methodology obligates a complete disconnect from the facts.]
The Hebrew University’s report
After these questions arose for me, I recalled that more than once I had read reports on various studies riddled with ridiculous flaws, only to find—upon reading the original article—that the problem lay in the journalistic report, not in the research. So I read the Hebrew University’s own brief report on this study. It is almost identical (the journalist copied the overwhelming majority of the summary—see below). However, I did find one relevant change. The academic report states that the “assumption” that finger thickness hasn’t changed over millennia is not just an assumption; it rests on other studies to which the authors refer in their article.
This indeed changes the picture somewhat and adds an important empirical dimension to this weighty sugya. But the need to rise from the armchair remains as unclear as before. Now the assumption that finger breadth hasn’t changed is the outcome of prior empirical studies (or at least supported by them; I didn’t check). Still, if we are equipped with this conclusion and combine it with U.S. Army data regarding current sizes, why is there a need to go into the field and measure jars? From those two premises alone one can infer the size of the tefach without getting up from the armchair (as is our custom in the a priori lab). Above I already discussed other possibilities—namely, that the study aimed to confirm an anthropological or historical hypothesis rather than to test the halakhic-historical claim about the tefach’s size—and I won’t return to that here.
I admit that if I were writing a serious review of this study, I would have had to read the scientific article itself (from the archaeological journal BASOR). I didn’t, because the topic doesn’t interest me enough, and the summaries I read did not whet my appetite. Therefore I must phrase my conclusion cautiously: in light of these reports, it seems the empirical research was superfluous. There was no need to get up from the armchair to reach this conclusion. But you are welcome to read and comment in light of the article itself.
You may then ask why I bother to write this column at all. The answer lies in methodological and logical lessons—in developing an appropriate stance toward various studies and, even more so, toward the journalistic reports about them. I therefore turn to the takeaways.
Lessons on the logical and scientific plane
Science, as distinct from mathematics, is built from empirical information and its logical analysis. The results must include some factual information, and that information doesn’t emerge from logic but from factual premises and the generalizations used in the analysis.
Note, logically speaking, that if we have a valid argument inferring some conclusion X from the set of premises {A, B, C}, then if we add further premises (say, D and E), the argument’s validity is preserved. For example, if I assume that all frogs have wings and that the table before me is a frog, I can infer that my table has wings. Now add the premise that Trump will be elected President of the United States today for a second time. The argument remains valid, of course (only it now contains a superfluous assumption; it would remain valid without it).
Returning to our study, the researchers’ conclusion relies on two premises: 1) the size of the tefach in the U.S. Army today is 89 mm; 2) the size of the tefach hasn’t changed over the last several millennia. From this one may infer: the Talmudic/Biblical tefach is also 89 mm. Indeed, even if we now add the measured widths of jar necks, and perhaps the assumption that they were made by men, and if you like also the premise that a full moon is now shining over Kamchatka, the argument remains valid. Only these additions contribute nothing to it—neither the Kamchatka premise nor the measured jar-neck widths. By the same token we could add the premise that the jars were made only by women, and that women’s hand-breadth changed sinusoidally across the years, with the period dividing the time since then to now with remainder 1—the conclusion would still remain in force.
This problem in their argument is scientific, not logical. It’s unclear why empirical work was required here, rather than sufficing with an a priori armchair study (or: why they’re stealing our laboratory’s livelihood).
Lessons on the journalistic plane
Here we have a common phenomenon: copying a report from the institution directly into a newspaper and presenting it as journalistic coverage. If they had copied verbatim and presented the piece explicitly as a text composed by the Hebrew University, there would have been some honesty. But presenting a spokesperson’s text as a journalist’s report on what occurred at the institution, in my view, violates basic journalistic norms. A journalist should critically examine the facts and their meaning and report on them independently. Imagine what we would say if we heard that a journalist transcribed a text issued by a politician’s spokesperson and presented it as a journalistic report on an event involving that politician (a daily occurrence, of course).[3]
The reasons for this widespread phenomenon are mainly the journalist’s laziness; but in scientific contexts it also reflects the journalist’s inability to examine the matter (because it requires experts). Yet in this case it would have been quite easy to check and pose the researchers some tough questions about their study, since even I—no expert in empirical archaeology (recall, my expertise is a priori armchair research)—managed to do so.
It’s worth knowing—many are unaware—that the appearance of an academic study in the popular press is a status symbol, no less than publication in prestigious journals. I recall that when I was in the Physics Department at Bar-Ilan, the department bulletin board regularly displayed clippings from the popular press reporting on our researchers’ findings. It’s no wonder that scholars and institutions pursue journalists to get their research into the general media—and journalists, of course, oblige (a win-win). This is a lesson for us as media consumers: how we should relate when we read about “groundbreaking” research in various fields. This is especially true in areas (like mathematics or physics) where the journalist lacks the knowledge and capability to truly vet the “breakthrough.”
One more note on armchair research in evolution: the case of finch beaks
In chapter four of my book God Plays Dice, I illustrated the phenomenon of a priori field studies (that is, field studies whose results can be predicted from the armchair) that are very common in the field of evolution, using the Grants’ research on the beaks of finches.[4] To clarify my claims about the tefach study, I’ll describe here the Grants’ experiment and briefly discuss its relevance.
The book The Beak of the Finch describes the fieldwork of Peter and Rosemary Grant in the Galápagos Islands in the Pacific (not far from where Darwin himself worked), mainly on Daphne Major. This work is considered a classic evolutionary field study, and the riveting (and very enthusiastic) book describing it even won a Pulitzer Prize. The Grants visited Daphne Major every year for about twenty years and tracked the development of the finch population on the island. They consistently measured several physical parameters of the finches—such as beak length, wing length, and so on. They found that over those twenty years—and even less—significant changes occurred in several parameters, and they even identified the reasons for those changes. The study demonstrated the evolutionary process in action, and contrary to the common view that evolutionary change requires thousands or millions of years for each step, it turned out—surprisingly—that a relatively small number of years suffices to sample such a process. For our purposes here I’ll describe one of those changes and the explanations found for it.
Chapter five describes the drought of 1977 and its consequences. On the island a plant called Tribulus was widespread; it scatters its mericarps which, after rain, sprout new Tribulus plants. Inside the mericarp are several seeds that can serve as food for finches. But to the finches’ misfortune, these mericarps usually hide under stones, and the common finch struggles to move them. In a normal year the finches do not eat those seeds, since more accessible plants are available. The Tribulus mericarps are hard to crack and are thus a low priority. But as a result of the drought almost all other plant types disappeared, and the finches were forced to subsist on the Tribulus mericarps. In 1973 the finches could hardly crack the hard shell of the Tribulus mericarp, and even those that did paid in great effort and time. Once the soft, accessible seeds vanished, the birds had to contend with the hard mericarps. The medium and small finches could not cope and almost all perished for lack of food. Only finches with strong, longer beaks—able to handle Tribulus mericarps—survived. The finch numbers declined steadily, and in parallel the average beak length and strength of the survivors increased. Thus the drought eliminated certain finch species (such as cactus finches) and selected for stronger, tougher beaks. The average beak length increased by about five to six percent compared to its pre-drought average. Note that such small variations in beak length and strength were what separated those that survived from their fellows who died. Thus far this is natural selection. Afterwards evolution operates: the survivors mated and their offspring were born with beaks as strong as their parents’ (genetics).
We must now ask: what was truly new in this field study? What did we learn at the conceptual level? Seemingly, this result is entirely banal: in a drought, only the hard seeds remain, and those that survive are precisely those able to crack them. Up to this point it’s a tautology. Add to this the principle that those who do not eat die—which doesn’t strike me as particularly groundbreaking—and the genetic datum that beak length is indeed heritable, and the end result is still a tautology. Thus, even without any observation, given the circumstantial facts (the drought, the weather resistance of Tribulus, and the varying capabilities of beaks), simple logic would lead any child to expect these outcomes.
True, without those observations we might not have known that beak length and strength are traits inherited genetically from parents to offspring—but that is a finding that belongs to genetics rather than to evolution per se. One could have reached that result by direct study, unrelated to evolutionary questions (by examining sample and control groups of finches and their offspring). This result does not belong to pure evolution but to its scientific periphery (genetics, etc.). No one disputes that genetics is an empirical science—i.e., falsifiable or confirmable. My debate in the book concerns only the principle of the survival of the fittest. Imagine we already knew that genetic fact that beak length is heritable; the study would seem to lose any theoretical significance.
To see clearly that the thesis proven by the Grants is a tautology (I defined it there as a “practical tautology,” without elaborating here), let’s present the matter as a logical argument:
Claim A: There was a drought.
Claim B: If there is a drought, plants disappear, except for a few hard seeds.
Claim C: Not all birds can crack hard seeds (it depends on their beak length and strength).
Claim D: Those that cannot crack hard seeds (i.e., whose beaks are too weak) have nothing to eat and die.
Claim E: Those that remain alive are precisely those that managed to crack such seeds (i.e., those with strong beaks).
Claim F: Beak strength and length are genetic traits passed from parents to offspring.
Conclusion: The beak strength and length of the offspring will increase after a drought.
It’s easy to see that, given the six premises, the conclusion follows by strict logical inference. This raises the question: what did we learn from the Grants’ study? Claims A–E are banal, self-evident facts that teach us no general principle about nature. No one seriously suggests that the study’s conclusion is that there was a drought that year, or that those who don’t eat die. Claim F is a genetic fact that could be discovered in the lab (not necessarily in the field), and in any case it is not the study’s main novelty. The conclusion, finally, is a simple logical consequence of those six claims.
Weiner himself sensed the problem, and quotes Raymond Pearl (p. 76 of the book):
“According to the opinion of many, surprisingly many, including some quite eminent names in science, it is all the same to show that something is logically necessary and to show that it actually exists. If the rules of formal logic are satisfied, they imagine that the truth has been revealed. No further proof is required. As everyone knows, such an approach has already, in effect, brought the whole theory of evolution to an intellectual bankruptcy…”
Those “eminent men of science” whom Pearl cites are entirely right. It is like a study showing that if there are ten finches on an island and six more arrive, then when we count the finches the total will be sixteen. Thus we have confirmed the (physical, not mathematical) law that 6+10=16. According to Pearl and Weiner, we should not think that if mathematics says so, there is no value in an observation demonstrating it in practice. Alternatively, the Grants’ study is like taking different triangles drawn on paper and measuring their angles to test whether their sums are 180 degrees. That too is a field test of a (practical) tautology. Is there any point or value in such a study? I have serious doubts.
In the evolutionary context it serves, of course, the propaganda needs of a defensive theory and the shoring up of believers’ confidence against their creationist critics. In the context of the biblical tefach, the study looks like conceptual confusion (had it been conducted by religious people I would have thought it too was meant to bolster faith). Substantively such studies are unnecessary. The Grants’ work offers at most a demonstration of evolutionary processes, but I see no substantive conclusion arising from it.[5]
When examining an empirical armchair study, it is advisable to structure the argument as I did here (and above for the tefach). With such a logical structure before us, we must ask which premises are known in advance and which are subject to empirical test. One can treat some premises as known and leave the others; then, if the expected conclusion is obtained, it corroborates the remaining premises. Thus, for example, had we not known there was a drought on Daphne Major, the study could have corroborated that. Had we not known that stronger beaks crack hard seeds more successfully, the study could have corroborated that. But if all the argument’s premises are already known independently prior to the study, then such research has no significance beyond psychological reinforcement for believers. We could have reached the conclusion without getting up from the armchair.
Incidentally, these very days in our A Priori Armchair Research Laboratory, we are considering expanding into evolution, gender studies (though there, all departments everywhere mainly do armchair research), psychology, household management, space science, nuclear physics, computational biology, political science, strategy and governance, history, literature, neuroscience, and more. Consider this column a call for donors—and may the listener find it pleasant.
[1] Thus it is presented in the Hebrew University report mentioned below.
[2] I’ll just note that yesterday I received a post from a well-known businessman who mocked the rabbis’ concern with the correct blessing for a krembo. He wondered at the useless, ridiculous topics to which wise people devote themselves in the 20th century. I replied that his scorn should have been directed at those who devote their lives to television shows—their production, viewing, and critique—and even to politics and other pointless subjects that occupy almost the entire secular public. That strikes me as far more ridiculous. But now I thought perhaps I should also direct him to these studies—some of which he may even be funding. There he can see that even our academy engages burning issues like why jar necks were made 89 mm wide in 10th-century BCE Israel. Shame on the rabbis who deal with the blessing over a krembo cookie instead of devoting their talents and energies to investigating the reason for fixing jar-neck widths…
[3] See, for example, Kalman Liebskind’s comments about the Wikipedia entry “Esther Hayut,” where the site’s editors were asked by the court system’s spokespersons to copy into it text written by their office.
[4] There it was part of my claim that evolution is a tautological theory that is not falsifiable (and therefore, of course, necessarily true). Survival of the fittest is a valid logical-analytic argument.
[5] For this reason, evolutionary researchers consider it very important to demonstrate such a phenomenon and watch it in action. This can have a non-trivial effect on one’s willingness to consider the blind process as an option. As Dawkins explains at length in his book (p. 169ff.), observing an evolutionary process can raise awareness of this option, which we tend to dismiss out of hand. But that claim is problematic, since it is a psychological effect, not a result of scientific significance.
Discussion
A. Regarding Grant's study, do you think it is possible to say that some or all of the assumptions (b-e), although they are reasonable and probably correct, were not known to us beforehand? Or at least were not formulated in that way? Many times the benefit of an observation lies in its contribution to developing the hypothesis, and if so, from the perspective of the explanations that came afterward, it does indeed seem that the field study was unnecessary. But in fact we would not have reached those supposedly a priori conclusions had we not had field results that we wanted to explain.
B. Still on this matter, have there not been some important scientific advances from the fact that someone tried to check whether assumptions that armchair philosophers regarded as absolute truths really hold in reality? There can be countless explanations for why the actual result would differ from what we thought, and there is also some value in the fact that someone checked it and saw that it really works.
I did not disparage him, only his words, which indeed deserve disparagement.
A. These are general statements. This is certainly possible a priori, since we do not know everything and there are hypotheses that are confirmed experimentally. But in order to claim that this is what is happening here, you have to point to the assumption that was not clear and that they came to test. In my opinion there is no such assumption here.
B. That only says that it is worthwhile to do such studies (perhaps we will get a surprising result that one of the assumptions we thought was correct is not so), but it does not show what we learn from them. I ask again: what did we learn from the Grants' research? That genetics really works? Why not do a study that tests adding oranges into a basket or the sums of angles in triangles?
Scientific theories can sound nice, correct, and logical on paper, yet not match reality (which in the end is what we want to investigate in physics/chemistry/biology). Sometimes people forget to take some factor into account, are unaware of another factor's existence, etc.
Therefore it is important to do studies that will confirm our theories.
If one were actually to measure the angles of giant triangles on Earth, one would discover that the sum of the angles is not necessarily 180, because that is not the geometry of our world, and we would learn something new about the world.
Likewise, in the finch study, we might have discovered that this is a society that takes care of its weaker members (strong finches crack seeds for the weak ones too), and then the effect would not have occurred.
In short, it makes sense to conduct experiments to confirm theories or at least find support for our theory, and nature can be surprising (after all, many groundbreaking theories emerged from experiments whose results did not match their predictions even though they were based on accepted theories).
That point has already come up above in David Vitzner's comment.
I did not say there is no value in such an experiment, only that one learns nothing from it. We would learn something from it if it refuted one of the assumptions we thought were correct. But it did not refute anything. So what did we learn from it? Try to point out what we learned from the tefach experiment or from the finches (did we discover that there is no altruism there? Even that is not necessary). Why not conduct an experiment in which we measure the sum of the angles in a triangle, or walk along two parallel lines and check that they really do not meet?
Regarding the study, the idea is simple: once it was proven that there is an exact measure like four fingers today, it is not reasonable to assume that five fingers of the past equal exactly four of today.
I'm not buying it. After all, we are not talking about the kinds of precision you are speaking of. In any case, even without that, my argument still stands.
In the words of the Tzelach mentioned above,
why did he understand that the size of thumbs had diminished only since the time of the sages of the Talmud,
and not since the time of the Rambam,
who also estimated by fingers the size of a vessel containing 43 and one-fifth eggs, and did not find a contradiction between the two measurements?
I don't know
They wrote explicitly:
"They identified traces of the biblical measure 'tefach.'"
That is: they discovered that the size of the tefach (already known) had a direct engineering significance: the diameter of the jar openings. "And its length falls within the range of the different estimates previously given for the measure of the tefach."
It is not clear what all the complication is about.
1. I was not able to read the whole article because it is only for people subscribed to the journal. In any case, in the summary that is open to everyone they write that they came to provide explanations for the correspondence between the men's tefach and the size of the jar openings.
2. Regarding Grant's research, you have simply proven all of evolution logically. If so, why do we need proofs of evolution at all?
I did not prove all of evolution, only the survival of the fittest. See my article and the book God Plays Dice.
Why
Regarding the archaeological study – in my opinion one needs to read the original article to understand what was done there. It does not seem to me that the authors of the article were trying to discover what the ancient tefach measurement was, and I would not be surprised if, from the researchers' perspective, their innovation was some interesting detail about the jar industry (that there was a standard for the width of the opening – not a trivial thing; jars today have openings in all sorts of sizes), and that this standard width matched a very common unit of measure and was apparently made according to it. To me this is a nice and interesting detail for someone interested in archaeology – and it is not merely a trivia detail. The structure of pottery vessels is a very important tool in dating strata, and such a discovery, that there is such a distinct characteristic for pottery from the tenth century, could be of great importance in that context, or in the context of identifying forgeries, and I assume in other contexts as well – I am not an archaeologist, so I do not know. In any event, the popular presentation of the article does not tell us very much about its novelty (even if it is done on the university website. Universities also have PR departments, and they too have heard a thing or two about clickbait).
Regarding the finches – I have not read the book, but in my opinion the excitement does not stem from some enormous novelty or from finding proof of evolution; there were more than enough proofs in the seventies. It seems to me more like a situation in which a nineteenth-century mapmaker gets to go up to the International Space Station and see that all the coastlines and continents that he spent his whole life measuring and drawing with all kinds of sophisticated tools and painstaking work of collecting and calculating do indeed look as he predicted. Until people got to space, nobody *saw* what the continents looked like. Everyone knew, no one was surprised to discover that they looked as we had thought after all the work invested in it, but there is something stirring and wondrous in the possibility of simply seeing the theory that you inferred from meticulous collection of facts and much thought taking place before your eyes. Here too, in my opinion, this is not about a sensational novelty but about amazement at watching evolution in action. Even if, when one thinks about it, perhaps we should not be surprised by the process that happened with the finches, there was still a unique combination of circumstances here that made it possible to see evolutionary change taking place before our very eyes within just a few years. For someone who until now had to imagine these processes, to infer their existence with some degree of certainty – I assume this is a special and exciting experience.
Of course, what I wrote about the finches does not make what happened there a sensational scientific novelty. My purpose is to explain why they bothered to write a book about it, and why they got excited about this observation (aside from the fact that this book is apparently an excellent popular introduction to the theory of evolution, and that is no small thing).
Indeed, the interpretive part of the article is armchair science. However, in truth, in the article itself they do not present things as a finding that proves what the ancient tefach measure was (I skimmed the article quickly, so perhaps I missed it). They simply describe the jars, and in the interpretive paragraph they elaborate on the above hypotheses as to why this measure was used consistently (and they note that, Obviously, without written findings it is impossible really to prove this kind of theory, and therefore:
"we would like to leave it as a possible theory".
).
I agree with all of that. As stated, my criticism is mainly of the report and not of the original article, which I did not read. Regarding the finches, of course you are right that this is where the excitement comes from. But one must not let the excitement spoil the line and lead us to think that we learned something from this study (see the first talkbacks above here).
Good. As stated, I did not read the original article, and I was not criticizing it.
The study on the finches indeed did not teach us anything new, but it did confirm a conclusion that had already been reached.
This strengthens the assumption that evolution on a small scale really does occur in practice and is not only theoretically possible (and as noted, not everything that appears expected in theoretical analysis actually happens in practice).
I would add that it is important to publish such studies not only to strengthen confidence in this conclusion in general, but specifically as a counterweight to studies that will not find it (for statistical reasons or because of malfunctions, etc.)
So I do not understand what the criticism is about.
(By the way, a study of the sum of angles in a sufficiently large triangle on Earth could teach us that the Earth is not flat. Some have done such studies over larger areas in order to discover whether there is high spatial curvature or something of the sort; I do not think they found anything.)
These claims have already come up. I did not criticize the study but those who thought it teaches us something (mainly the reports). There is indeed value in confirmatory studies. Of course, there is also significance to the question of what exactly they confirm.
In my opinion, the article about the finches was meant to show that serious changes (relatively speaking) can occur in a population *very quickly*. In the case of the finches (or the moths in the English Industrial Revolution), literally within a not very large number of years.
Suppose a population whose beak length was 80 meters, and within 20 years the beak length is 200 meters (I'm just throwing out numbers). The point here is the short time in which these things happen.
If I come to a certain country and murder everyone who is not blond, close the gates, and return after a hundred years, presumably the percentage of blonds in the population will increase a great deal. This has nothing to do with evolution, nor is it natural selection in real time.
More generally, regarding scientific studies like this one about the tefach, it is only to look for headlines and pass the time with the institute's/university's budget.
By the way, perhaps this is silly, but I have always seen something in common between the scholarly kollel fellow and the modern researcher: that the only difference between the Haredi yeshiva man immersed in Talmudic sugyot and unwilling to confront existential questions because he is afraid of them, and the science researcher who will never reach a revolutionary point because of his weakness, is that the latter enjoys an encouraging social environment without anyone shouting, 'the king is naked,' and we will continue to suffer a flood of researchers and studies (even in the exact sciences) with no need or novelty for humanity… so long as everyone feels they are engaged in something called truth.
With God's help, 19 Marcheshvan 5781
The discovery that the jars, though of different sizes, had a uniform opening diameter corresponding to the measure of a 'tefach' – is certainly interesting. It may be assumed that the need to match the opening to the width of a man's palm, which is larger than a woman's palm, was meant to allow men as well to engage in cleaning the jars; therefore the jar had to be built so that a man too could put his hand into it. After all, dishwashing is not counted in the Mishnah among the seven labors a woman performs for her husband (and as explained in the Gemara, 'a woman does not become a rinsing agent' 🙂
The fact that there is a difference in body size between men and women raises an interesting question. The measures in the Bible and in the words of the Sages that express the size of body parts – such as finger, span, thumb, tefach, cubit, and the like – were they calculated according to the average size of the male body or of the female body? Or perhaps there were measures for men and measures for women? And perhaps this is the meaning of the expression 'by a man's cubit' – by the cubit of a man, which is larger than the cubit of a woman.
If there were indeed separate sizes for man and woman – perhaps one could thereby resolve all the difficulties and seeming contradictions that arise from the sources regarding the different sizes.
'Armchair hypotheses' cannot lead to conclusions – but they certainly can be an 'opening of a tefach' for renewed study of the sources and the archaeological finds, study and examination that will confirm or refute the 'armchair hypothesis.'
With blessing, Yosef Tzvi Bidani, Levite trumpeter
Paragraph 3, line 1
… resolve difficulties in this way…
"Perhaps the jar-makers back then were actually women, except that the thickness of women's fingers did change over the generations? Alternatively, perhaps these were five fingers of men and not four, and the thickness of their fingers (and perhaps also of the women's) increased?"
Maybe. Maybe you wrote sensible things in the original, but in the transition to the internet they were replaced with nonsense? Maybe.
The question is whether you mean possible or probable. If you meant possible, the answers to both questions are yes. If you meant probable, the answers to both are no.
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… larger than the cubit of a woman.
By the way, I saw a video of Rabbi Sherki about the size of an olive-bulk kezayit (which I am unable to find right now) in which he argues that the size of the olive did not change at all according to archaeology, and that every halakhic authority who wrote that the olive is much larger than it is today simply had no olives in his country.
With God's help, 15 Kislev 5781
To Yishai – greetings,
It is difficult to attribute the positions of the decisors that a kezayit is about half an egg to unfamiliarity with reality. After all, Rabbi Yosef Karo, who lived in Tzfat, writes in his Shulchan Arukh (Orach Chayim, sec. 486): 'And some say that the measure of a kezayit is about half an egg' – so in Tzfat Maran did see olive trees.
The source of the position that a 'kezayit' is about half an egg is in the sugya in Keritot, which says that one cannot eat more than two 'kezeytim' at once. The problem is that there are other sugyot from which it appears that a 'kezayit' is less than a dried fig-bulk, and on that basis the Rambam wrote that a 'kezayit' is less than a third of an egg, and the Rashba wrote that a 'kezayit' is less than a quarter of an egg.
To reconcile the sugya in Keritot, one can say, like Rabbenu Tam, that the sugya in Keritot is speaking of hard foods that do not dissolve easily, and therefore it is not possible to chew together more than two olives at once, even though in terms of volume the gullet has room for more.
The proof from the archaeological findings, in which the olive pits found are not larger than the olives of our day, is brought by Prof. Mordechai Kislev in his article on 'Kezayit' in Techumin, vol. 10. However, in my humble opinion it can be rejected by saying that there were varieties in which the flesh was larger even though the pit was the same size, just as among dates today there are dates of the 'Medjool' variety whose flesh volume is very large relative to the pit. Since in the days of Hazal the oil in olives was a central commodity both for eating and for lighting, it stands to reason that they invested in developing oil-rich varieties.
A concise summary of the sugya – you will find in Rabbi Chaim Navon's article, 'How Many Olives Are There in a Kezayit?', on the Asif website.
With bright Hanukkah blessings, Yaron HaLevi Borlai-Wertheimer
The Shulchan Arukh's view is based on Rishonim who preceded him and wrote this, so they did not really know olives. By the time of the Shulchan Arukh they had already begun to say that the sizes had changed, etc.
To Yishai – greetings,
As I explained above, the position of the Rishonim that the olive is about half an egg is based on the testimony of the authors of the sugya in Keritot that the gullet cannot hold more than two olives. And since in Yoma it is explained that the gullet holds about a hen's egg – it follows from the above that the olive is about half an egg, or at any rate more than a third of an egg.
One can say that the sugyot disagree, or that Keritot is speaking of food that is not soft, such that it is difficult to chew more than two olive-bulks together (and that is what one must say according to the Rambam and the Rashba, who hold that a kezayit is less than a third / less than a quarter of an egg), but from the straightforward sense of the sugya in Keritot it emerges that the kezayit is close to half an egg, and Hazal certainly saw olives.
And I have already brought the example of the Medjool variety among dates, whose flesh is far larger than the flesh of other varieties even though the pit is the same size, so it is not far-fetched that among olives too there were flesh-rich varieties that reached about half an egg, as the sugya in Keritot testifies.
With blessing, Yevorakh HaLevi
R. Yosef Karo also followed Rabbenu Tam's view regarding nightfall, even though he lived in the Land and saw that it somehow did not fit all that well (although apparently he did not yet know that there exists a reasonable interpretation of the Gemaras without Rabbenu Tam's approach). Maran apparently was not strong on consulting reality before accepting the authority of the ancients. And see also Sukkah 22b, Tosafot s.v. kezuzah, where they humorously brought proof from a verse for the everyday claim that a large distant object appears small to us, and what verse could fit such a matter better than "and we were in our own eyes as grasshoppers."
In my opinion it is not humorous. It is Tosafot's way to cling to verses and not make use of observations of reality.
With God's help, 15 Kislev 5781
To Ratziyo' – greetings,
Just as regarding the 'kezayit' the basis is the testimony of the Gemara in Keritot – so regarding nightfall, the source is the Gemara in Pesachim, which says that just as between dawn and sunrise there is the travel time of four mil, so too between sunset and the emergence of the stars there is the travel time of four mil.
Without being too much 'in the know,' I understand from the Gemara in Pesachim that the emergence of the stars described there parallels 'dawn.' And just as dawn is the beginning of the glimmering of light in the east – it seems that the ’emergence of the stars' in Pesachim is the last light at the western horizon.
This also makes sense. The rotation of the earth, which causes the sunlight to begin glimmering before sunrise – likewise causes its disappearance to occur by the same gradation after sunset, and that same span of time between the first light and sunrise – will also be between sunset and the last glimmer of light.
I recall seeing in Orot Chaim by R. Chaim Druck that nowadays, when the nights are illuminated by splendid electric light – we do not discern the remnants of light at the western horizon. Only someone who is in a place completely dark in terms of electric lighting – can discern the remnants of daylight, which disappear completely only 72 minutes after sunset.
With blessing, Shzionalizmus
I read Post 63, where you say that you do not disparage our rabbis. But here you really did disparage the Noda BiYehuda.