[Avodah] zilzul shabbat

[Micha Berger via Avodah]

On Thu, May 28, 2015 at 12:00:22PM -0400, Sholom Simon via Avodah wrote:
: I'm having a hard time wrapping my head around the suggestion that a
: kosher lamp is zilzul shabbas. 

That's okay, it's just a hava amina we raised here. No one AFAIK actually
banned kosher lamps over zilzul Shabbos. The question was why a Kosher
Switch (that claims to not even be grama) would be zilzul and not the
Kosher Lamp.

And then, many (most? the vast majority of posqim?) do not believe
it actually avoids gerama, including the author of Shemiras Shabbos
kehilkhisa.

: Isn't just a nice (and -- significantly
: -- *safer*) way of covering a lamp? 

Well, every case where one would discuss zilzul Shabbos would be one
where there wasn't a more easily defined problem. So every discussion
could be "isn't it just".

I think the difference is that a kosher switch would mean being able to
turn or off anything, whereas the Kosher Lamp is more limited, being a
specific appliance.

...
: Why do the rabbis deem the following to not be a
: case of zilzul yom tov: cooking a large pot of food on the afternoon of
: yom tov rishon, "in case people might stop by", and "I'll eat some of
: it" knowing there will be leftovers? 

I would guess that similarly, because it's of limited utility. It doesn't
totally destroy the concept of an issur of cooking on Yom Tov.

Tir'u baTov!
-Micha

-- 
Micha Berger             The fittingness of your matzos [for the seder]
micha at aishdas.org        isn't complete with being careful in the laws
http://www.aishdas.org   of Passover. One must also be very careful in
Fax: (270) 514-1507      the laws of business.    - Rav Yisrael Salanter