[Avodah] goy vs chiloni

[Saul Mashbaum]

RETurkel

> The question was if a chiloni opened the front door by pushing an
> electronic button could one enter the building? (lets assume CI for
> electricity)
> He answer was that yes because one did not have direct benefit from
> the chillul shabbat but what he call "mavriach ari",

RCLunz

<<.  The term mavriach ari I am
familiar with as a concept within Baba Kama and the laws of compensation, ie
if somebody chases a lion away from your property , do you have to pay
them or not?,
What does this have to do with hilchos shabbas?  Where is it found used it
in hilchos shabbas?  >>

The concept  is hasarat hamoneah, a form of gramma.
This basic idea is that of preventing something from preventing
something else. Two negatives make a positive, and the desired action
is performed, albeit very indirectly. In the case cited, the chiloni
prevented the door from preventing the person's entry.

This concept is the basis of the gramma instruments of Machon Zomet.
For example, a photoelectric beam periodically prevents current from
flowing  in an instrument. Blocking the beam, in and of itself a
non-melacha, will (inderectly) enable the current to flow after  short
time, enabling the instrument to function.
Poskim of Machon Zomet consider this "negative gramma" the ideal form
of gramma for the instruments it designs for hospital and military
use, where there is ample halachic basis for leniency in HS.

This subject is discussed in considerable  halachic and technical
detail by R. Dr. Mordechai Halperin, and others, of Machon Zomet in
many books and articles.


Saul Mashbaum