since he can interpose between himself and the graves and go and eat the food that comprises the eiruv without contracting ritual impurity.

GEMARA: Rabbi Yoḥanan said: One may not learn from general statements, i.e., when a general statement is made in a mishna using the word all, it is not to be understood as an all-inclusive, general statement without exceptions. This is true even in a place where it says the word except. Even in that case, there may be other exceptions to the rule that are not listed.

The Gemara notes: From the fact that Rabbi Yoḥanan said: Even in a place where it says except, this proves by inference that he was not relating to the general statement made here in the mishna, which uses the word except. To which mishna, then, was he relating when he formulated his principle?

The Gemara answers: He was relating to a mishna found there: With regard to all time-bound, positive commandments, i.e., mitzvot that can only be performed at a certain time of the day, or during the day rather than at night, or on certain days of the year, men are obligated to perform them and women are exempt. But positive commandments that are not time-bound, both women and men are obligated to perform.

Is it a general principle that women are exempt from all time-bound, positive commandments without exception? But there is the commandment to eat matza on Passover, the commandment of rejoicing on a Festival, and the commandment of assembly in the Temple courtyard once every seven years during the festival of Sukkot following the Sabbatical Year, all of which are time-bound, positive commandments, and nevertheless, women are obligated to perform them.

Similarly, are women obligated in all positive commandments that are not time-bound? But there is the commandment of Torah study, the commandment to be fruitful and multiply, and the commandment of redemption of the firstborn, all of which are positive commandments that are not time-bound, and nevertheless, women are exempt from them. Rather, Rabbi Yoḥanan said: One may not learn from general statements, even in a place where it says except, because it is always possible that there other exceptions to the rule.

Abaye said, and some say it was Rabbi Yirmeya who said: We, too, have also learned a proof for Rabbi Yoḥanan’s principle from a mishna: They stated yet another general principle: Anything that is carried upon a zav is ritually impure. And anything on which a zav is carried is ritually pure, except for an object suitable for lying or sitting upon and a human being, which become defiled if a zav is borne on them. The following objection may be raised: And is there nothing else? But there is an object upon which a person rides that becomes impure, as explained in the Torah itself.

The Gemara first asks: What are the circumstances of an object upon which one rides? If he sat upon it, it is a seat. If not, how does it become defiled? What is there that is suitable for riding upon but does not fall into the category of something upon which one lies or sits? The Gemara answers: We say as follows: There is the upper part of a saddle, which becomes ritually impure as a riding accessory and not as a regular seat. As it was taught in the Tosefta: A saddle upon which a zav sat is impure as a seat of a zav, and the pommel, which is attached to the front of the saddle and used by the rider to maintain his position or to assist in mounting, is impure as a riding accessory. Therefore, we see that the general statement found in the mishna omits that which is suitable for riding upon. Rather, conclude from this that one may not learn from general statements, even in a place where it says except.

Ravina said, and some say it was Rav Naḥman who said: We, too, have also learned a proof for Rabbi Yoḥanan’s principle from the mishna, which states: One may establish an eiruv and merge alleyways with all kinds of food, except for water and salt. And is there nothing else? But there are truffles and mushrooms, which also may not be used for an eiruv because they are not regarded as food. Rather, conclude from this that one may not learn from general statements, even in a place where it says except.

We learned in the mishna: All types of food may be bought with second-tithe money, except for water and salt. Rabbi Eliezer and Rabbi Yosei bar Ḥanina both had the same tradition, but one teaches it with regard to eiruv, and one teaches it with regard to the second tithe.

The Gemara elaborates: One teaches this halakha with regard to the issue of eiruv, as follows: They only taught that one may not establish an eiruv with water or salt in the case of water by itself or salt by itself. But with water and salt together, one may indeed establish an eiruv.

And the other one teaches this halakha with regard to the issue of the second tithe: They only taught that water or salt may not be bought with second-tithe money in the case of water by itself or salt by itself. But water and salt mixed together may indeed be bought with second-tithe money.

The Gemara comments: The one who teaches this law with regard to the second tithe, all the more so would he apply it to an eiruv, i.e., he would certainly maintain that water and salt together are suitable to be used for an eiruv. However, according to the one who teaches this law with regard to an eiruv, it applies only to an eiruv; but with regard to the second tithe, no, it does not apply. What is the reason for this distinction? For the second tithe, we require produce, as stated in the Torah, and even when water and salt are mixed together they do not have the status of produce.

When Rabbi Yitzḥak came from Eretz Yisrael to Babylonia, he taught this law with regard to the second tithe. The Gemara raises an objection from the following baraita: Rabbi Yehuda ben Gadish testified before Rabbi Eliezer: In Father’s house they would buy fish brine with second-tithe money. He said to him: Perhaps you only heard this in a case where the fish’s innards were mixed with the brine. Since this mixture contains a small portion of the fish, the brine becomes significant enough to be purchased with second-tithe money. And even Rabbi Yehuda ben Gadish only said his statement with regard to brine, which is the fat of produce, i.e., because a certain amount of fish fat, which itself may be purchased with second-tithe money, is mixed in with the brine; but a mixture of water and salt alone may not be bought with it.

In response to this difficulty, Rav Yosef said: