WHEN ARE WE CONCERNED FOR ZUGOS?
(Beraisa): One should not have two acts of relations.
Question: We should say that he reconsidered to have relations again (they should not be counted together)!
Answer (Abaye): It means, one should not eat two things [or drink two cups or clean himself twice] and then have relations even once, lest he become weak and his Mazel sour.
(Beraisa): If one drinks an even number, he is responsible for his own death.
(Rav Yehudah): This is if he did not go out to see the market [between cups] - if he did, there is no problem.
Rav Ashi: I saw Rav Chinena bar Bivi go out to see the market after every cup.
Zugos is a problem only if he intends to travel afterwards - if he will remain at home, there is no problem.
(R. Zeira): Going to sleep is like travelling.
(Rav Papa): Going to the outhouse is like travelling.
Question: It is problematic even if he will remain at home!
Rava used to keep track [of the parity of his drinks] using beams (he always used to face the next beam on each successive drink to keep track of the number, even when he was going to remain at home);
Whenever Abaye drank one cup, his [surrogate] mother held two cups in her hands [to ensure that he will not drink an even number in all]!
Whenever Rav Nachman Bar Yitzchak drank two cups, his assistant held one cup in his hand; when he drank one cup his assistant held two cups in his hands.
Answer: Important people are different (Shedim try harder to harm them - for regular people who stay home, it is no problem).
(Ula): We are not concerned for Zugos if one drinks 10 [or more] cups.
This is like he taught elsewhere (some say that it is a Beraisa), that Chachamim enacted [to drink] 10 cups in Beis ha'Evel - if Zugos applied to 10 cups, Chachamim would not enact something that can be dangerous! (This is unlike Rava, who says that the cup of Berachah does not join for harm.)
Zugos does apply to eight.
(Rav Chisda and Rabah bar Rav Huna): 'Shalom' (any seventh, just like Shalom is the seventh and final word in the last Berachah of Birkas Kohanim) joins [to six] for good [to preclude being Zugos], but it does not join for bad (Zugos does not apply to a total of eight, 10...)
Zugos does apply to six.
(Rabah and Rav Yosef): "Vi'Chuneka" (any fifth - 'Vi'Chuneka' is the fifth and final word in the second Berachah) joins [to four] for good, but it does not join for bad (Zugos does not apply above five).
Zugos does apply to four.
(Abaye and Rava): 'V'Yishmerecha' (any third - this is the third and final word in the first Berachah) joins for good, but it does not join for bad (Zugos does not apply above three. Above, Rava justified why Chachamim enacted four cups and were not concerned for witchcraft, but in any case Zugos would not apply.)
Rava acted according to his teaching - he often dismissed Rabanan after they had four drinks.
He was not concerned, even though Rava bar Livai was harmed [after drinking four] - he was harmed because he used to ask questions while Rava was teaching [in public - this embarrassed Rava].
Rav Yosef: Yosef the Shed told me that Ashmedai, the king of the Shedim, is appointed over all Zugos;
Version #1: A king does not normally damage (we need not be so concerned for Zugos; the Beraisos warn against it on account of witchcraft).
Version #2: A king does whatever he wants - he may breach a fence to make a path for himself, and people cannot protest (we must be very concerned for Zugos).
Rav Papa: Yosef the Shed told me that Shedim kill on account of two (e.g. cups); they damage on account of four, but they do not kill;
They strike on account of two whether it was Shogeg or Mezid; they damage on account of four only if it was Mezid.
WAYS TO AVOID HARM
Question: If a person forgot and went out [after he drank Zugos], what should he do?
Answer: He should clasp his right thumb in [four fingers of] his left hand, and vice-versa, and say 'You (plural) and I are three' (therefore, you may not harm me on account of Zugos);
If he hears [anyone say] 'You (plural) and I are four', he should respond 'You and I are five', and so on;
A case occurred, the person went up to 101, and the Shed burst [from pain. Maharsha - all agree that Zugos does not apply past 100.]
Ameimar: The head of female witches told me that one who encounters them should say 'boiling excrement in torn baskets should be in your mouths, you female witches; your hairs should fall out, the wind should disperse your crumbs, spices and new saffron (all of these are used for witchcraft);
As long as Hash-m, myself and you had mercy on me, I did not come amidst you;
Now that I am amidst you, I see that my and your mercy on myself has cooled.
In Eretz Yisrael they are not concerned for Zugos;
Rav Dimi of Neharda'a was concerned even for an even number of lines scratched on a barrel (a sign of how much is inside); a case occurred, the barrel burst.
The general rule is - these Shedim only confront people who are [overly] concerned for them.
(Rav Dimi): A tradition from Moshe from Sinai teaches that one should be concerned for two eggs, two nuts, two gourds and two of another matter;
Chachamim were unsure what the other matter is, therefore they decreed about everything.
Various Amora'im said that Zugos applies only below 10, eight, six or four - this is only regarding Shedim, but any even number causes vulnerability to witchcraft:
Reuven divorced his wife; she married a grocer. Every day Reuven drank wine in that store, and she tried to harm him with witchcraft; she failed, because he was careful about Zugos.
One day he drank a lot; after 16, his mind was not so clear, and he ceased to beware of Zugos; she made him leave after an even number. An Aravi saw him and said 'this man is [like] dead!' Reuven grabbed onto a tree - it dried up [on account of the witchcraft done to him] and he burst.
(Rav Avira): Zugos does not apply to bowls of [cooked] food and loaves;
The general rule is - Zugos does not apply to something finished by man; we are concerned only for foods finished by Shomayim [that it is the 'other matter'. Chazon Ish - we see that it applies to wine! Rather, Zugos of foods finished by Shomayim are problematic no matter how they were eaten; other things are problematic only if the person did an even number of actions.].
Zugos does not apply to drinking in a store. (This regards Shedim - the above episode shows that it makes one susceptible to witchcraft.)
If one [ceased to eat or drink, and then] reconsidered [to have more], Zugos does not apply;
Zugos does not apply to a guest (he never knows how much he will get, therefore it is as if he reconsidered each time);
Zugos does not apply to a woman (she normally does not plan to drink a lot), unless she is esteemed.
WHAT JOINS REGARDING ZUGOS
(Rav Chinena brei d'R. Yehoshua): Aspargus (a drink made from cabbage; people drink it before eating in the morning) joins for good, not for harm.
Version #1 (Ravina): We are stringent about [Safek] Zugos (if one is unsure how much he drank, he drinks another with intent that it join only if he previously had an even number - otherwise, it is like reconsidering);
Version #2 (Ravina): We are lenient about Zugos (if one drinks more to be safe, this shows that he is concerned for them, which makes him vulnerable).
(Rav Yosef): Two cups of wine and one of beer do not join [to be considered three]; two cups of beer and one of wine do join;
A way to remember this - whatever is connected to something more stringent than itself is Tamei, whatever is connected to something more lenient is Tahor. (This is a Mishnah about a garment made from two materials - the more stringent material (i.e. it has a smaller Shi'ur to Mekabel Tum'ah) can complete the Shi'ur for the more lenient material, but not vice-versa. Wine is more important than beer, hence it corresponds to the more stringent one.)
(Rav Nachman): Two cups before the tray [of food was brought] and one cup with the tray join; one cup before the tray and two with the tray do not join.
Objection (Rav Mesharshiya): We do not need to fix (protect from Zugos) the tray, rather, the person - he drank three [in both cases]!
All agree that two cups with the tray and one after do not join, like the case with Rabah (someone drank two cups with the tray, and was afflicted; Rabah instructed to return the tray and then give him another cup to cure him).
(Rav Yehudah): All mixed drinks join [for good or bad], except for water [even hot and cold water is not considered mixing];
(R. Yochanan): Even mixed water joins.
(Rav Papa): This is only if hot water and cold water were mixed - but if both were cold or both hot, it does not join.