Eruvin 69-71  The Lomdus of “Bittul Reshus”

 
The main theme of this daf relates to the concept of  בטול רשות  and how and when it applies.
We have mentioned before that the mechanism of choice for multiple inhabitants of one courtyard is to make an עירוב חצרות  whereby food is set aside on behalf of everyone in one of the houses, symbolically “joining” them all into residents of the same domain.
This is of course a symbolic mechanism which does not in any way affect the actual ownership of the houses and shared courtyards, and serves merely as a reminder not to carry from a private domain to a public domain proper- something Chazal were concerned enough about to prohibit carrying from one private domain to another owned by different people in the absence of such an eruv.
This eruv can only be done before Shabbos, as doing it on Shabbos resembles מקח וממכר  (commercial activity.)
If one or more of the inhabitants did not participate in the eruv before shabbos, the eruv is essentially ineffective.
This is because although all those who participate in the eruv are considered as if they share each other’s houses as well as their share in the common courtyard, the courtyard is also owned by those who did not participate, and therefore subject to different ownership than the houses of the participants.
This means that no one can transfer items between their houses and the common courtyard or vice versa.
One solution available is the mechanism of בטול רשות , also referred to in the Mishna as נתינת רשות .
The relationship between these two phrases requires analysis in its own right-for one approach, see Rambam Pirush haMishnayos Eruvin 6/1, 6/3 and 6/4 who seems to understand that נתינת רשות sometimes refers to making the eruv and sometimes refers to בטול רשות.
Whereas the phrase בטול רשות  seems to indicate a one-way mechanism by which the owner removes himself from ownership, control, or some other connection to his share in the courtyard (or possibly also his house,) the phrase נתינת רשות seems to indicate a two-way mechanism similar to a gift where the owner “gives over” one of the above at least symbolically to the other inhabitants.
There is a debate between Beis Shamai and Beis Hillel as to whether this may be done on shabbos, and the Gemara explains that Beis Shamai view בטול  as a form of two-way transaction whereby the non-participants  give over their “authority” over the courtyard to the participants, effectively leaving the courtyard owned in its entirety by the participants and making the eruv effective.
Seeing as such transactions are forbidden on shabbos, it may not be performed on shabbos.
In contrast, Beis Hillel view this as simply  סלוק (removing oneself from authority), a one-way mechanism that achieves the goal of making the courtyard owned solely by the participants due to his share being irrelevant, rather than owned by them.
Such an arrangement is permitted on shabbos, and at first glance, it might appear to be a form of הפקר- declaring one’s property to be ownerless- once his share of the courtyard is ownerless, the others remain its sole owners and their eruv is valid/
However, there are limitations that apply to the rules of הפקר  that do not seem to apply here.
For example:
i.                    Hefker needs to be declared in front of three people )Nedarim 45a), yet one person can be מבטל רשות to 2 people, and there is no indication here that someone else needs to be present (Tosfos deals with this issue in Pesachim 4b)
ii.                  According to the view that one needs to be מבטל רשות to each one of the people who were included in the eruv, simply making one’s share הפקר is clearly not enough
iii.                Hefker removes all legal connection between oneself and the object, to the point that anyone else can perform a קנין  (transactional act) on it and acquire it. In addition, the person who declared it הפקר  would need to perform an official קנין  in order to reaquire it- doing so in one’s mind would not do the trick. In this case, there does not appear to be any ability on the part of those who benefit from this בטול to take legal ownership of the property, but the benefit is limited to symbolic permission to carry within the area “as if” they owned it. Furthermore, it does not seem that a legally valid קנין needs to be made by the original owner in order to cancel this בטול.
iv.                It is not at all clear that declaring something הפקר  on shabbos is permitted, as the Ramban points out (Pesachim 4a)- it could be included in the general prohibition of commerce.
 
The concept of בטול  can be found in various other areas of halacha, for example:
1.      בטול חמץ  – one is required to declare any chametz left in one’s possession before midday on erev pesach “nullified like the dust of the earth.”
According to Rashi (Pesachim 4b,) this seems to be a way of fulfilling the mitzva of תשביתו  (removing chametz from one’s possession) and Tosfos seem to understand that it is a form of הפקר that creates a situation where that mitzva is simply not relevant anymore
 
2.      בטול ע”ז – an item of idolatry may become permitted if it is nullified by the idol-worshipper- this can done by breaking part of it, possibly a sign of its lack of importance to the owner (see A.Z. 52b.)
 
Though all 3 usages of this phrase seem to share in common the idea that one is declaring or showing that the item is no longer of importance to him, there is no need to assume that the “lomdus” (logical mechanism) in all three is similar. It is very possible that בטול חמץ  is a real form of הפקר  which בטול עבודה זרה  is certainly not, and that בטול רשות  is something completely different.
After all the phrase בטול  is also used regarding  בטול תורה  (wasting time when Torah could have been studied,) בטול עשה and   (avoiding performing a positive mitzva,)  בטול and none of them have anything to do with הפקר or ownership.
More specifically, whereas בטול חמץ  and בטול עבודה זרה  seem to work on a biblical level to avoid the prohibitions of owning chametz on pesach or an item of idolatry, בטול רשות  is a rabbinical measure which might simply be meant to have a similar symbolic effect  to that of the eruv.
However, there are views in the Rishonim, principally that of the Ramban (Pesachim 4b,) who  seem (at least a first glance) to assume that all three work on a similar mechanism and thus attempt to leave הפקר  out of the discussion altogether.
Although a thorough analysis of the various views as to how these different instances of בטול  work is still required, it is clear that whatever explanation is offered will need to pass the test of the different rules Chazal prescribed for each of them, in the absence of some other “external” explanation for the rule in question. The topic is vast- I have barely scratched the surface of the many sugyas and mefarshim that relate to the topic.
 
 
These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.