This post was delayed by my desire not to be so critical of what clearly exhibits the consequences of a ḥareidi orientation. However, after further consideration the Torah-only philosophy reflected is so pernicious to topics in zemanim, I felt I have no choice but to address / confront.
To add more motivation, I noticed that bastion of fairness, Ha(aino)modia, failed to even mention Rav Adin Steinsalt Even-Israel ztl’s passing. Long after his detractors are at best a footnote to history, his seforim will still be valued.
I received a sefer entitled Z’manim on the Friday following Tisha B’av. I told my Rav that the yetzer ha’rah would have encouraged me to read it on Tisha B’av had it arrived a day earlier. After Shabbat, having read / skimmed the book I wrote back to my Rav that reading the sefer on Tisha B’av would have perhaps been permissible since it would only have added to the spirit of the day.
The author is a grandson-in-law of a prominent Rav who wrote an important sefer on zemanim, Munaḥ Yomah. This sefer, however, included something I never saw previously except in an advertisement – a haskamah with (only) a partial quote, omitting words. It read as follows: “This is a fascinating and scholarly review… and…” I wonder what was omitted before “and.” Beyond that, the word scholarly coupled with another haskamah from Rabbi Simcha Bunim Cohen seemed somewhat oxymoronic given normal use of the word scholarly. I would be more inclined to call Rabbi Cohen Open Orthodox before calling this sefer scholarly; yeshivish, (sadly) perhaps, scholarly never.
What causes my negative reaction? First, and fundamentally, the lack of reference to the science that provided an underpinning to ḥazal’s calculations of a fixed calendar. To say otherwise is in my mind (close to) kefirah. One example (of many) suffices. Ḥazal, like astronomers of their time knew that the exact period between “new moons” varied (considerably). In establishing the calendar, they used the average time between lunations, something they (and scientists of their time) approximated with 6 decimal place accuracy. It is critical to realize that knowledge of the average lunation came from science and not the halakhah / mesorah. We now know the average lunation not only to 6 but to 8 decimal places. To attribute slight imprecision to ancient science is hardly surprising, but to assign ḥazal’s imprecision to HlMmS, halakhah or mesorah borders on kefirah. (BTW the organization responsible for the bible codes episode, put out another similar and objectionable video on the time between lunations as well.) How ḥazal arrived at the molad / average time between lunations scientifically is necessary to better appreciate the source of the very minor error.
Second, to compare (partially and inadequately) Rabbi Adda’s tekufot to those implicit in the Gregorian calendar is either just bad judgement or inability to calculate accurately, (page 71). Those tekufot implicit in the calendar of Pope Gregory came over a thousand years after Rabi Adda and are much more accurate. Nowhere did I see any statement on the impact of Rabi Adda’s inaccuracy (at this point an approximate 5 – 6-day drift to a later date in the year caused by the calendar) and reasons it should not be of concern until a few thousand years from now. Without acknowledging the implication of a slightly longer year, its halakhic (non-) import cannot be addressed, a significant omission. Instead, the issue is simply omitted.
Third, the discussion of the Gaon’s critique of Rabbeinu Tam, is at best incomplete. Its implications go well beyond what was discussed. The Gaon’s ḥush and scientific knowledge in addition to his compelling logic are all not optional but essential to understanding his attacks on the opinion of Rabbeinu Tam.
Fourth, the author’s assertion of the absolute need for a dateline is simply false. RIZM ztl and RTPF ztl disagree; modern logic (and their insightful he’orot based on the positions of rishonim and aḥaronim) supports their halakhic position.
It is of importance to note that well before Rambam, in geonic times, an Arab astronomer details a roughly accurate version of the fixed calendar created by the rabbis, expressing his amazement at its brilliance. Ḥokhmah ba’Goyim timtzah.
Many of the papers included on this site address all the issues raised.