Taharos, Chapter 6, Mishnah 6. This mishnah sits inside a wider discussion of the two domains, reshus harabbim and reshus hayachid, and of how a case of sfeik tumah is resolved in each one. It comes in two parts. The first part sharpens the rule itself, and the second part opens up a question that has been hovering unspoken over everything until now: what earns a place the title of public domain, and what makes a place a private domain?
Until He Says
The mishnah teaches: "Safek reshus hayachid, tamei ad sheyomar lo nagati": a doubtful tumah that arose in the private domain is ruled tamei until the person says, "I did not touch." The stringency of the private domain stands as long as the doubt stands. Once he is able to clarify matters and state that he had no contact with the source of tumah, the ruling of tumah falls away. The Bartenura adds that the wording is not confined to touching in particular; any statement that resolves the doubt works, such as his declaring that he is not tamei at all.
The reverse side follows: "Safek reshus harabbim, tahor ad sheyomar nagati": a doubtful tumah in the public domain is ruled tahor, and it stays that way until he himself says, "I did touch." There the leniency holds until he removes the doubt by admitting contact with the tamei object.
So What Is a Public Domain?
Until now we have been using the terms reshus harabbim and reshus hayachid as though their definitions were obvious, and in truth they are not obvious at all. The mishnah now begins to supply the definitions, and the following mishnayos will continue the project.
"Eizo hi reshus harabbim? Shvilei Beis Gilgul": which is a public domain? The paths of Beis Gilgul. What is Beis Gilgul? Following our practice of learning with the Bartenura wherever possible, he understands it as rounded, rolling ground that people are unable to cross. What exactly Beis Gilgul is remains a large machlokes. Some more recent approaches take the words at face value as the name of an actual location, a spot in Eretz Yisrael that would have been familiar to the Tannaim, much as one of us today might casually say that New York City is a reshus harabbim. We simply do not know with certainty.
The mishnah continues: "v'chein kayotzei bahen", and other places of that sort, and rules that such a place is "reshus hayachid l'Shabbos u'reshus harabbim l'tumah", a private domain regarding Shabbos and a public domain regarding tumah. This is a striking piece of information: a single place can carry two different classifications at once, private for one area of halachah and public for the other.
Rabbi Elazar's Dissent
Rabbi Elazar disagrees about which case belongs where. He holds: "Lo huzkaru shvilei Beis Gilgul ela shehem reshus hayachid l'kach ul'kach", the trails of Beis Gilgul were singled out for the opposite reason, because they are a private domain in both respects, for Shabbos and no less for tumah. The case that carries the split classification, according to him, is another one entirely: "hashvilim hamefulashin l'boros v'l'shichin v'l'me'aros v'l'gitos", the trails that open out in the direction of water pits, ditches, caves and winepresses. Regarding those, he says, the place is private for Shabbos and public for tumah.
Two Different Systems
At this point the obvious question presses itself: how do we define a public and a private domain for tumah, if the definitions do not track the ones we know from Shabbos?
The Shabbos picture is one we already know. A reshus hayachid there is a space closed in by walls and held by one owner, a place with something like real title to it, and set against it is the reshus harabbim. The Bartenura wants a precise reading here: our mishnah's phrase reshus hayachid l'Shabbos does not describe a genuine reshus hayachid, but a karmelis. Altogether there are four domains. The Torah itself acknowledges reshus harabbim and reshus hayachid. Beyond them there is the makom petur, an area of no halachic weight at all, such as the air above a river, which barely registers as a domain. And there is the karmelis, which on the level of Torah law is a private domain, yet the Chachamim saw that in practice it bears none of the marks of one and none of its character, so they gave it the status of a public domain by rabbinic decree. Worth filing away for later. Our mishnah, though, did not wish to muddy the water: since on a Torah level the place genuinely is a private domain, and since the term is being placed opposite reshus harabbim l'tumah, the mishnah opts for the straightforward wording, even though rabbinically the place is handled otherwise.
Tumah begins somewhere else altogether. The domains of tumah and taharah are learned out from the parashah of sotah, and in the sotah context questions of ownership and enclosure are not the deciding factor. Privacy is. A spot that is closed off and secluded counts as a reshus hayachid. A spot that may be walled in yet is in no way hidden, a busy thoroughfare with people streaming past all the time, counts as a reshus harabbim, since no one would suspect a woman of adultery in such a setting. That is the whole key, and it will continue to unfold in the mishnayos ahead.