Please permit me to ask an historical question which I find very perplexing concerning the well known halachic issue of the size of the olive.
There seems to be some kind of discrepancy that implies that the Rishonim in France and Germany may not have actually seen an olive firsthand, so they used the baseline of an egg as a reference point for the halachos involved.
According to some articles I have seen, there were and still are olive trees in the south of France, including one specific tree which is among the oldest olive trees in the world.
Why couldn't the Rishonim who lived in the southern part of France, bring olives to the northern part of France (or similarly to Germany) where the Baalei Tosfos were?
Furthermore, it is well known that the Rosh had to flee Germany to avoid capture and ransom by the King, as happened to the Maharam from Rottenberg, and he escaped southward to Spain, where he met the Rashba with whom he had previously corresponded in various Responsa.
The Rosh remained in Spain for the rest of his life, and obviously he would have seen olives there, so why doesn't he mention this in any of his commentaries or Responsa, and also never notifying his son who remained behind in Germany, Rabbeinu Yaakov who wrote the Turim, and who quotes his father the Rosh throughout the volumes of the Tur, but this particular important detail about the actual size of olives is never mentioned.
Theoretically the Rosh and the other Rishonim could have asked the Rishonim such as the Rashba in Spain to tell them the size of an olive, or even trace the outline of an olive on paper, or perhaps even send an olive from Spain to France on one of the frequent caravans.
Assumably the Romans also brought olives from Italy to France and Germany.
To add to this already complex mystery, there were many great Chachomim and Poskim who either lived in Eretz Yisroel and traveled to Europe, or vice versa.
Yet, despite this, with only one exception, there is not a single mention of the actual size of an olive becoming known to those who were in Europe, or had emmigrated from Europe.
This singular exception is quoted in the name of one of the Rishonim Rabbeinu Shimshon ben Shmuel, (at the moment I cannot find any information about him), who traveled to Eretz Yisroel from Ashkenaz in the mid 1300's, and wrote that he saw there that even 3 olives were not as large as half an egg, or, according to another quote, even 6 olives were not as large as an egg.
However, his account was apparently not mentioned by any of the Poskim.
Another detail to investigate, would be if in the countries where there were no olives, they were still able to light the Chanukah menorah with olive oil.
Therefore the question must be asked, why didn't any of the scholars from the lands where olives were grown, inform the scholars of other countries where olives were supposedly not found, of the real size of an olive?
Why didn't any of the scholars living in Europe simply ask the scholars living in Eretz Yisroel or Spain or Italy, to tell them the size of the olive?
For example, the Beis Yosef who was born in Spain, actually lived in Bulgaria in southeastern Europe after his family was expelled first from Spain and then from Portugal.
On his eventual journey to Tzfas he also lived in Greece and Turkey.
After settling in Tzfas around 1535, he then began authoring his famous Shulchan Aruch which he published in Venice Italy in 1565.
At that time Tzfas was the center of Judaism and many of the Gedolim had settled there.
The Beis Yosef was appointed to the Beis Din of the Mahari Berav who was considered the Gadol HaDor, and also had his own Yeshivah with around 200 talmidim.
Just from these brief biographical details, it is obvious that the Beis Yosef himself was familiar with actual olives from Spain, Eretz Yisroel, and Italy.
As a Posek he was also familiar with the opinions of Tosafos and the Rosh and so on, yet in the Shulchan Aruch which he wrote in Eretz Yisroel, he does not mention anything about the actual size of olives, just the measurements according to eggs.
About 200 years later, in the late 1700's, the Chida who was twice the Shadar for Chevron, travelled extensively throughout Europe, his mother's family was Ashkenazi who had settled in Jerusalem with the aliyah of Rabbi Yehudah Chasid, and he even stayed at the home of the Pnei Yehoshua, and also at the home of Rabbi Saul of Amsterdam who was a grandson of the Chacham Tzvi.
The Chida was also aware of the dilemma of the olive and the egg, and certainly could have informed the Sages of Europe of the actual size of an olive, or he could have brought some olives with him from Eretz Yisroel to show them.
He would later settle in Italy, and again could have informed the relevant Poskim in Europe of the actual size of the olive.
The talmidim of the Baal Shem Tov who settled in Eretz Yisroel, and afterwards the talmidim of the Vilna Gaon, could have informed those back in Europe of the actual size of the olive.
These examples should illustrate the ongoing mystery of the size of the olive.
Menachem Kwartowitz , Lakewood, NJ USA
Shalom Menachem,
Thank you for raising such a carefully researched and historically rich question. The breadth of sources you cite and the precision of your detail show real diligence, and it is a pleasure to engage with so thorough a presentation.
I do not claim to possess a decisive answer regarding the absence of recorded shipments of olives from the Mediterranean to northern Europe; nevertheless, several considerations may clarify why explicit reports do not surface in the Halachic literature.
Many Poskim, including the Shulchan Aruch, describe the Shi'ur of a k'Zayis almost exclusively by converting it into fractions of a Beitzah. One reason is linguistic: in large parts of Ashkenaz olives were scarce, whereas every household knew eggs, so legal language gravitated toward the familiar Beitzah. Rav Yosef Karo certainly handled olives in Spain and Eretz Yisrael, yet he still formulates the Shi'ur in egg-terms. Besides addressing readers who might never see an olive, this reflects his consistent practice of quoting the Rambam verbatim, and the Rambam himself expresses the measure in eggs.
More fundamentally, the classic Shi'urim arise from a textual tension. Kerisos states that the Beis ha'Beliʿah holds at most two olives, while Yoma says it holds one egg. The Ba'alei ha'Tosfos reconcile the two by fixing the k'Zayis as 1/2 Beitzah; later authorities such as the Tzelach and Chazon Ish expand the number on similar textual grounds, for example, by arguing that modern eggs have shrunk. Once the Shi'ur is anchored in reconciling two Sugyos, presenting a physical olive cannot resolve the issue; at most it moves the debate to whether olives or eggs have changed.
A well-known story captures how the physical object can seem secondary. When a woman once showed Rav Baruch Ber Leibowitz an actual chicken gizzard, he reportedly exclaimed, "Dos iz der heyliger pupik?" - as if meeting, for the first time, the tangible organ he had long analyzed in the Gemara. The anecdote illustrates how halachic discussion can become so layered that the specimen itself feels almost incidental.
Empirical evidence is not always straightforward. A fresh olive loses volume within days, and when pickled its size contracts further. Even had olives reached the study halls of Germany or northern France, they would likely have arrived in that diminished state, returning the discussion to written description rather than direct measurement, this time, though, based on eye-witnesses which is a bit better, but might not be a game changer.
I hope these remarks shed some light on the matter and contribute, in some small way, to the impressive investigation you have already begun.
Kol Tuv,
Aharon Steiner
P.S. The Rabeinu Shimshon ben Shmuel you mention is almost certainly Rabeinu Shmuel ben Rabeinu Shimshon mi'Shantz, a French Ba'al Tosfos who joined his friend, Rabeinu Yonasan of Sunil, in 1211 on a journey to Eretz Yisrael.
Thank you for the reply.
Please permit me to respond to the p.s., an apparent misunderstanding has fallen here, the name I mentioned was R' Shimshon ben Shmuel, not the reverse, and he apparently lived around 1365, he is also called ish Yerushalayim.and wrote a sefer called "Yerios Izim" and there is another sefer called "Kitzur Mordechai," which one source attributes to him, but this might be an error, since another source says that it was written by R' Shmuel ben Aharon from Selestat, which is a different name.
Shalom again,
Thank you very much for the clarification. In my first quick reading I missed that you indeed wrote Rabeinu Shimshon ben Shmuel rather than the reverse. From the context of your note, which mentions travels to Eretz Yisrael and observations on the k'Zayis, I assumed you were referring to Rabeinu Shmuel ben Shimshon of the Ba'alei ha'Tosfos. Your correction is of course accurate, and I appreciate it.
Thank you once more for your enlightening questions.
Kol Tuv,
Aharon Steiner