[Avodah] Birkas haChama

[Micha Berger]

On Tue, Aug 26, 2008 at 11:19:48PM +0000, kennethgmiller at juno.com wrote:
: The Artscroll "Bircas Hachama" goes into it. As I recall, there were
: two views in the gemara on how to calculate these cycles, one being
: more accurate mathematically, and the other being the one we use. It
: seems that Chazal deliberately opted for a less-accurate calculation,
: because it has the advantage of being more useful to the average person,
: who would be unable to calculate the other one.

(We discussed this in 2005. RET hit it in Daf Yomi in
http://www.aishdas.org/avodah/vol15/v15n006.shtml#14 (

When it comes to pi or the solar year WRT tal umatar, the issue is
one of precision. There is no perfect answer, and thus the question is
simply how precise need we be. RAM's presentation makes Shmuel's tequfah
inferior in kind. I'm trying to show that it's necessary to approximate --
one differs from the other only in degree.

In this case, I would agree with RAM that when making a shiur choosing
between orders of precision, why be more precise and less easy to
implement? I /would/, if the mitzvah is derabbanon, or if someone can
show me a ra'ayah that these things are or aren't halakhah lemosheh
misinai like other shiurim.

In the case of birkhas hachamah, it's not just a matter of calculation,
it's a matter of whether the mitzvah would be done once in 28 years
or using R' Ada's year of 365d 5h 997c 48r and only doing it once in
2,068,417 years -- ie not at all. Even rounding to the nearest cheileq
we would only be making it once in 907,201 years -- still effectively
not at all.

There is no other approximation that we tended to use that would allow
us to commemorate maaseh bereishis in Nissan at all that is more precise
than Shemu'el's.

Which ties into my insisting one not confuse relying on tequfas Shemu'el
with relying on the Julian Calendar. If one can leverage secular calendars
for this, the Gregorian calendar's approximation of the year would have us
saying birkhas hachamah every 401 years. May be too far apart to preserve
the custom, but still multiple times during the course of human history.

Other questions may be in either of these two categories, or may be in
a third one... The human mind's "gut instinct" isn't always all that
mathematical. Who said the din is about the physics of the situation,
rather than our perception of it? Long timers here know it wasn't me.

: Other examples include:
: - Urine is diluted with a reviis, regardless of how much urine it is.
: - Halachos about eating in the afternoon on Erev Shabbos and Erev YT
:   totally ignore how much one ate in the morning, or what time one expects
:   to finally eat at night (at the seder, for example).

The mius-keit of urine, as to whether one may daven near it, is clearly a
psychological issue, not one of the chemistry of urine. And how full you
are after a meal, and whether you are slighting Shabbos or YT, is as well.

On Tue, Aug 26, 2008 at 09:57:52PM -0400, Zev Sero wrote:
: You're missing the point, which is that nothing special happens that
: morning, so what is it exactly that we're making the bracha on?

According to the berakhah, Oseh Maaseh Bereishis. Which is said on
numberous things that remind people of creation -- from the "yehi or"
suddenness of lightning to the motion of the yabashah of an earthquake
to birkhas hachamah. The berakhah is on the recollection, not the event.

Is it a birkhas nehenin that requires the trigger be real? Shoulnd't a
takanah made to artificially recall the creation of the sun count as well?

Tir'u baTov!
-Micha

-- 
Micha Berger             I long to accomplish a great and noble task,
micha at aishdas.org        but it is my chief duty to accomplish small
http://www.aishdas.org   tasks as if they were great and noble.
Fax: (270) 514-1507                              - Helen Keller