A Murky Dispute
‘Water Does Not Affect Its Status’
(Shabbos 100a)
Abaye on our daf says that a person standing in a reshus harabim who throws an object into a water-filled pit which is ten tefachim deep and four tefachim wide has violated Shabbat because he has thrown an object into a reshus hayachid. However if that same pit would be filled with fruits and vegetables the person will not have violated Shabbat by throwing an object into it since the pit is no longer a reshus hayachid. What’s the distinction between water and produce? There are two explanations.
Visibility
The Ramban explains that filling a pit with produce cancels its status as a reshus hayachid because the pit’s walls, which as a rule must be visible, are obscured. Water, on the other hand does not obscure the pit’s walls since it is transparent. Therefore, the pit retains its reshus hayachid status.
Usage
The Me’iri maintains that a pit laden with produce loses its status as a reshus hayachid because it can no longer be used. It no longer really has the minimum ten tefachim depth. On the other hand, the presence of water does not completely hinder the pit’s use since water is fluid, not solid. Items can, in theory, be placed in a water-filled pit.
Turning On Its Head
The Magen Avraham (Orach Chayim 345:10) and Sefas Emes note a practical difference between the Ramban’s and Me’iri’s views in the following scenario: Suppose a pit is filled with solid items that don’t obscure the pit’s walls – glassware, for example. According to the Ramban, the pit should retain its reshus hayachid status. However, according to the Me’iri the pit loses its reshus hayachid status since the objects inside it prevent it from being used.
One More Turn
The Pri Megadim (cited by the Eishel Avraham, ibid. sk11) notes that if the pit is filled with murky water or wine, it would also lose its reshus hayachid status according to the Ramban because its walls are not visible. According to the Me’iri, however, the transparency of the liquid is of no consequence. Even when there is no visibility of the pit’s walls, the pit remains a reshus hayachid because it still can in theory hold items.