Gemara

4a (Mishnah): Brothers who are partners [in an inheritance]:

If they are obligated to give a Kalbon (a small coin added when giving Machtzis ha'Shekel), they are exempt from Ma'aser Behemah;

If they are obligated to take Ma'aser, they are exempt from Kalbon.

4b (R. Chiya): We should say that there are four distinctions:

They are obligated in both if they divided the money, but not the animals;

They are exempt from both if they divided the animals, but not the money;

They are obligated in Kalbon and exempt from Ma'aser if they divided everything;

They are obligated in Ma'aser and exempt from Kalbon if they did not divide anything.

Bechoros 56b (R. Elazar): This is when one brother took nine animals and the other took 10 (worth the same amount).

If each took the same number, we say that each received his proper inheritance (for Yesh Breirah), so they are obligated in Ma'aser.

(R. Yochanan): Even then, we do not say that this is his proper inheritance. (Ein Breirah.)

Bava Kama 69a (R. Yochanan): If something was stolen and the owner did not despair, neither the thief nor owner can make it Hekdesh;

Contradiction: R. Yochanan said that the Halachah follows an anonymous Mishnah!

(Mishnah): Tzenu'im (very pious people) would take coins and say 'whatever (Revai) was gathered from my field is redeemed on these coins.' (If one can redeem what is not in his Reshus, one can be Makdish it!)

Answer #1: The text should say 'whatever will be gathered is redeemed on these coins.'

(Beraisa - R. Yehudah): In the morning, the owner says 'what the poor will gather today is Hefker';

R. Dosa says, at evening he says 'what they gathered is Hefker'.

We must switch the opinions of R. Yehudah and R. Dosa. We know that R. Yehudah holds that Ein Bereirah!

Eruvin 36a (Mishnah): If a Tevul Yom flask (it was immersed today) was filled with Ma'aser that is Tevel [to Terumas Ma'aser], and the owner said 'it should be Terumas Ma'aser at dark', this takes effect. If he was Me'arev with it, it is invalid.

Yevamos 93a: R. Yanai's sharecropper used to bring to him Peros every Erev Shabbos. Once he delayed coming. R. Yanai took Ma'aser from his own fruits on the fruit he expected to receive.

Demai (Mishnah 7:5): If one had Tevel figs in his house, and he is in the Beis Midrash or field, he says 'the two figs that I will separate, they are Terumah. Ten are Ma'aser Rishon, and nine are Ma'aser Sheni. If they were Demai, he says 'what I will separate tomorrow is Ma'aser Rishon. The rest of the Ma'aser is next to it. What I made Ma'aser is Terumas Ma'aser. Ma'aser Sheni is in the north [or south], and it is redeemed on the coins.

Rishonim

Tosfos (69 DH Ela): R. Yochanan holds that Ein Breirah, unlike a Stam Mishnah! Perhaps he holds Yesh Breirah when the person explicitly stipulates.

Tosfos (Gitin 25b DH Divrei): In Bava Kama, the Gemara could have answered that R. Yochanan holds Yesh Breirah when the person explicitly stipulates. It preferred to suggest that the text is 'was collected', like it says in a Beraisa.

Ran (Gitin 13a DH v'Ika, citing the Ramban): Breirah is only when one stipulates about two things, e.g. "the one that will leave first", or "the two Lugim that I will separate." He stipulates about both wives, or every two Lugim in the barrel. A stipulation about one matter, e.g. "write a Get for her if she will leave first", or "if the Chacham comes to the east, my Eruv is in the east" works even if Ein Breirah "On condition that father will want [the Kidushin]" depends on Breirah, for it depends on someone else. We hold that such Kidushin works according to Rav Yosef, who explains that it means "on condition that father will not object."

Poskim

Sha'agas Aryeh (93): R. Yehudah (Yoma 13b) holds that the Kohen Gadol marries a second wife, and divorces both wives before Yom Kipur. He stipulates that one is divorced if her co-wife will not die [on Yom Kipur], and the other is divorced on condition that he enter the Beis ha'Keneses. Why must he marry and divorce, and disqualify a woman from Kehunah? (One may not do so if he can avoid this - Yevamos 44a.) He should be Mekadesh the second on condition that his current wife dies, and divorce his [current] wife on condition that he enter the Beis ha'Keneses? If his wife will die, he will enter, so retroactively she was divorced and the Kidushin took effect. If his wife will not die, he does not enter, so the Kidushin did not take effect. Further, he could be Mekadesh "after my wife will die." The moment she dies, the other Kidushin takes effect. He can do also Chupah on Tanai. I say that this is like Ayo, who says that R. Yehudah holds that Ein Breirah (Eruvin 36b). However, all agree that a Tanai 'on condition that Ploni not die' works, since no action is required. The Ran brought from the Ramban that "on condition that father will not object" works when no action need be done. The Tanai 'that I enter the Beis ha'Keneses' does not require Breirah, because it depends on him. Rashi (Gitin 25b DH ul'Chi) says that something b'Yado (that he could do), e.g. Kidushin on condition that I give to you 200 Zuz, is surely a good Tanai. We require Breirah only to make something take effect retroactively from when he stipulated, e.g. for an Eruv to take effect, or for a Get to be Lishmah. All agree that one may stipulate for something to take effect at a future time. This does not depend on Breirah.

R. Akiva Eiger (ibid.): Tosfos (69b) says that R. Yochanan does not say Ein Breirah when the person explicitly stipulates. If so, what was the Gemara's question? Tosfos (Gitin 25b) says that the Gemara could have said so (that it is not difficult for this reason), just it preferred to change the text. This is a weak answer. What was the intent of the one who asked? Rather, the Mishnah says 'what was collected', which is unlike R. Yochanan, who holds that one cannot redeem what is not in his Reshus. We answered that the text is 'will be collected.' It is redeemed just before it is detached. If so, it must be redeemed before it is detached, i.e. it is clarified retroactively.

Noda bi'Yehudah (1 EH 91): A woman can say 'the one Ploni will choose, he will be a Shali'ach in place of me to receive my Get.' This is even according to the opinion that Ein Breirah. Even though 'whoever wants to receive my Get is my Shali'ach' does not work, there she did not designate anyone. Here, she designated the one that Ploni will pick. One who says 'whoever hears my voice should write a Get' works. This is not a full proof, for there, the Shelichus is finalized once he speaks and the hearer hears. Here it is not finalized until Ploni chooses. Perhaps this requires Breirah. However, I say that Breirah applies only to a matter for which it would not suffice if it took effect at the time it is clarified, from then and onwards. Rather, it needs to work retroactively. E.g. he tells a scribe to write a Get for the wife he will choose after it is written. It must be Lishmah (for her) at the time it was written. If one will choose the Terumah after he drank some of the wine, it must be Terumah before he drank. (If not, he drank Tevel.) Here, it suffices that he be a Shali'ach at the time he receives the Get. A husband can make a Shali'ach to give a Get, and the Shali'ach can make a Shali'ach afterwards. The husband never specified who will be the new Shali'ach! This is not a proper proof. There, the first Shali'ach is in place of the husband. It is as if the husband appointed the second Shali'ach. We cannot say that Ploni is in place of the woman, for a Shali'ach Kabalah (to receive a Get) cannot appoint another Shali'ach to receive, for this is Mili (a kind of Shelichus that cannot be transferred to another Shali'ach).

Noda bi'Yehudah: Rather, I bring a proof from one who told 10 'write, sign and give a Get to my wife.' One writes, two sign and one gives, even though the husband did not specify which. This is because it need not be clarified who will do so at the time the husband spoke. This does not require Breirah. Bava Kama 69b connotes unlike this. It infers that R. Yochanan holds that Yesh Breirah, since he says 'what will be picked' is redeemed. There, it need not be clarified from the time he spoke. Why does this depend on Breirah? Tosfos (DH Ela) asked that R. Yochanan is unlike the Stam Mishnah, and answered that R. Yochanan does not say Ein Breirah when the person explicitly stipulates. If so, what was the Gemara's question? Tosfos (Gitin 25b DH R. Meir) says that the Gemara could have said so (that it is not difficult for this reason), just it preferred to suggest that the text is 'was collected.' This is a weak answer. What was the intent of the one who asked? Rather, we first asked against R. Yochanan, for he holds that one cannot redeem what is not in his Reshus, for the Mishnah says 'what was collected.' We answered that the text is 'will be collected.' It is redeemed just before it is detached. If so, it must work retroactively.

Chazon Ish (Demai 9:10 DH Mishnah): If the text of Mishnah 5 does not say 'tomorrow' [in the Reisha], and the stipulation works due to Breirah, also in the Seifa regarding Demai it is due to Breirah. If the text says 'tomorrow', and it is a Tanai, the Tana holds that Ein Breirah. If Yesh Breirah, the separation tomorrow is merely to fulfill the Tanai, and it is not relevant to the Heter of the Tanai. Perhaps a Tanai of Breirah and a Tanai to permit are different. A Tanai of Breirah does not require an action afterwards, just designation. This is what he stipulates about. A Tanai to permit makes Terumah at the time of separation. When one makes a Tanai of Breirah, he says 'that I will separate in the future', i.e. to designate and clarify the Tanai (what he made Terumah now - PF.) In a Tanai to permit, he says 'what I will separate', with intent to make it Terumah. Therefore, even according to the opinion that Yesh Breirah, he makes it Terumah on Shabbos, and his initial declaration is only in order to permit. He does not declare the Terumah and Ma'aser to be in the north or south, for afterwards it will be difficult to be sure that what is in the north then was in the north at the time of the declaration.

Chazon Ish (ibid.): Even according to the opinion that Ein Breirah, he can stipulate that the Ma'aser take effect on Shabbos at the time he separates. The Noda bi'Yehudah (1 EH 91) says so, and R. Akiva Eiger (1:159) brings so from the Sha'agas Aryeh. This is clear from Bava Kama 69. 'What was collected' does not depend on Breirah, even though he stipulates in the morning (Tosfos 69a DH Kol). Perhaps in any case it is considered tithing on Shabbos, since the Tanai is fulfilled through separation. Even though one may separate during the week to take effect on Shabbos (Eruvin 36a, Yevamos 93a), there, there was no separation on Shabbos. Actually, if Ein Breirah, one cannot declare Terumah now based on a Tanai, for we require Shireha Nikarim (one can distinguish the Terumah from the remaining Chulin). Tosfos (Eruvin 37a DH Meichal) says that if Ein Breirah, he drank Chulin. Rashi (Chulin 14a DH Osrin) said that retroactively, he drank Terumah. It seems that he means that it was destined to be Terumah. We cannot say that what he drank truly was Terumah.