Commento su Makhshirin 2:12

זיעת בתים טהורה – it does not make the seeds susceptible to receive ritual uncleanness.

Introduction Our mishnah deals with sweat when does it cause something to be susceptible to uncleanness and when does it not.

זיעתו טמאה – that it is on account of the [drawn] water, and specifically it comes with drawn water, but not if it comes with water that is fastened to something that is unclean that are not susceptible, for even though that currently they are however detached, it was not done intentionally.

The sweat of houses, of cisterns, of ditches and caverns does not cause susceptibility to uncleanness. Sweat from buildings and other structures, meaning the moisture formed on their outsides, has not been moved by a person and therefore it does not cause susceptibility to impurity.

A man's perspiration does not cause susceptibility to uncleanness. Human perspiration similarly does not cause susceptibility.

If a man drank unclean water and perspired, his perspiration does not cause susceptibility to uncleanness. The sweat that comes out of his body is not accorded the same status as the unclean water from which it comes, because he already ingested it. It counts as sweat and therefore it does not cause susceptibility.

If he entered into drawn water and perspired, his perspiration causes susceptibility to uncleanness. In this case, since he didn't ingest the water but rather bathed in it, his sweat is considered as if it came from the drawn water. Therefore, it causes susceptibility.

If he dried himself and then perspired, his perspiration does not cause susceptibility to uncleanness. If he then dries himself, he has gotten rid of the water from the drawn water and his sweat is considered to be from his body. Therefore, it no longer causes susceptibility.

מרחץ טמאה – of drawn waters.

The sweat of an unclean bath is unclean, The sweat that comes from an unclean bath of water has the same status as the water in the bath. It is unclean. It also causes susceptibility, for unclean liquids always cause susceptibility.

זיעתו טמאה - it makes the produce susceptible and defiles them.

But that of a clean bath comes under the law of ‘if water be put’. The sweat of a clean bath is not inherently unclean, but it does cause susceptibility to impurity.

וטהורה – meaning to say, the sweat coming from a bathhouse is clean, as for example, the bathhouse of the waters of a fountain which are not drawn water, this is subject to [the laws of] “If water be put” (Leviticus 11:38: “But if water is put/וכי יותן מים upon seed grain [and any part of a carcass falls upon it, it shall be unclean for you],” for the sweat makes the produce susceptible [to receive ritual uncleanness].

If there was a pool in a house, the house sweats because of it if the pool was unclean, the sweat of all the house which was caused by the pool is unclean. The purity of the sweat of a house with a pool in it depends upon the purity of the water in the pool. If the pool is unclean, then the sweat is unclean and will cause susceptibility. If the pool is clean, the sweat of the house is considered as coming from the pool and it will cause susceptibility. This is different from general sweat from a house which does not cause susceptibility, as we learned in yesterday's mishnah.

אם טמאה – the pool, all the sweat [of the walls] that the house produces on its account makes it susceptible and defiles it, but where it is not on its account, it is the sweat of [the walls of] the house and is pure.

ברזל טמא – that came from shards of impure vessels.

Two pools, the one clean and the other unclean: The sweat near the unclean pool is unclean, And the sweat near the clean pool is clean, And what is at equal distance [from both pools] is unclean. Things that sweat and are closer to the unclean pool are considered unclean, for we assume that the sweat came from the unclean pool. The same is true in the opposite case. If something was right in the middle of the two, the ruling is stringent due to the doubt, and the sweat must be considered unclean.

שבללו (that one smelted) – that one planed/scraped and combined with pure iron that comes from the wrought metal/polished block (see also Tractate Kelim, Chapter 11, Mishnah 1),

Unclean iron was smelted with clean iron: If the greater part [came] from the unclean iron, it is unclean; If the greater part [came] from the clean iron, it is clean; But if there was half of each, it is unclean. The mishnah now goes on to consider other cases which have the same literary structure as section one. This structure will continue through the end of the chapter, and will cover topics that diverge from the main topic at hand the ability of liquids to cause susceptibility to impurity. The first topic at hand concerns pure and impure iron that have been smelted together. The status follows the majority and if they are of equal amount, the rule is stringent.

אם רוב מן הטמא טמא – the Sages decreed on metal vessels that were defiled and broken and were melted and made of them vessels that would return to their former defilement until he would sprinkle [water] upon them on the third and seventh [days] and immerse them and their sunset would come.

Pots owned by Israelites and non-Jews used for passing water: If the greater part is from the unclean [urine], it is unclean; If the greater part is from the clean [urine], it is clean; But if there was half of each, it is unclean. Jewish urine is considered clean but gentile urine is considered impure due to rabbinic law (see Niddah 4:3). In this case, if the mixture is equal, then the rule is lenient because the impurity of gentile urine is only derabanan (bet you never thought you'd be reading about that!).

גסאריות (pots) – like a kind of pots that were made to urinate in them. And in the Arabic language we call them BISRIASH.

Waste-water, in which rain had fallen: If the greater part consisted of the unclean water, it is unclean; If the greater part consisted of clean water, it is clean; But if there was half of each, it is unclean. Waste-water is assumed to be impure. Again, the rule follows the majority and if they are of equal amount the rule is stringent.

שישראל ונכרי מטילים לתוכן – urinate into them. And the urine of a heathen is ritually impure, for they (i.e., the Sages) decreed that they would be like those with a flux/gonorrhea for all their matters.

When [is this the case]? When the waste-water came first; but if the rain water came before [the waste-water], it is unclean whatever the quantity [of the rain water]. The above is true if the waste-water was there first. In such a case, the rainwater went into the vessel against his wishes and therefore this water is not susceptible to impurity. If there is a majority of rainwater the whole vessel will be pure. However, if the rainwater went in first, then he was probably collecting it, and it went in to his desire. In such a case, the rainwater is susceptible to impurity. When any amount of waste-water falls in, it will defile it.

מי שפיכות (water that is poured out, dirty water) – water that they washed with and they pour them - outside, and they are under the presumption of being ritually impure.

אימתי- are dirty waters/waters that are poured out voided in a majority [of rain water].

בזמן שקדמו – that they (i.e., the dirty waters, water that is poured out) [came first] and afterwards the rainwater increased [as a majority] and purified them.

אבל אם קדמו מי גשמים – even if a bit of rain water fell upon them, they are impure.

המטהר את גגו (if one scrubs his roof) – We have the reading "המטהר את גגו" /if one purifies his roof. But there are those who have the reading, "הטורף את גגו"/if one scrubs his roof, meaning that he plasters his roof with plaster or lime to even it out. And the water that one places upon it when one purifies it or when one merely plastered it, they pour it (i.e., the water) and they purify itr, and similarly the water that one washes with them his clothing.

If one flattened out his roof or washed his garment and rain came down upon it: There are two situations in this mishnah. The first is that one is flattening out his roof and he pours out waste water at on the completed roof to smooth it out. The second is laundering a garment. In both of these cases the water being used is impure. This water is then mixed in with rain water and the question is whether the water is impure such that when it falls on food it would defile it.

וירדו עליהן גשמין – which are pure waters. And the roof or the clothing drips water.

If the greater part consisted of the unclean water, it is unclean; If the greater part consisted of the clean water, it is clean; But if there was half of each, it is unclean. As in the previous cases, the status of the water follows the majority. If it is half and half, then we rule strictly and it is unclean.

אם רוב מן הטהור טהור – as for example, if it would drip thin drops at the outset and afterwards it would drip thick drops, it is sure that the majority [of the water] is from the pure [water].

Rabbi Judah says: if the dripping increased, [it is clean]. If the dripping from the roof or the laundered garment increased after the rain flow, then we can assume that the rain water was greater than the impure water from flattening the roof or laundering the garment. In this case, any water that subsequently comes from the roof or garment will be considered pure.

אם הוספיו לנטף – that the drops hurry to descend one after another more than at the outset, it is pure, for they certainly are the majority, and even if the drops themselves are larger from what they were at the beginning. But the Halakha is not according to Rabbi Yehuda.

רוחץ בה מיד – on Saturday night, and one does not need to wait until it warms up, for since that the majority are heathens, it was warmed with the knowledge of the heathens.

Introduction A Jew is not permitted to benefit from work done for another Jew on Shabbat, but a Jew can benefit from work done for a non-Jew on Shabbat. If a Jew does forbidden work on Shabbat and another Jew wants to benefit from that work, he/she must wait after Shabbat however long it would take for that work to be done. For instance, if I make a roast on Shabbat (Heaven forbid!) and then my wife (who is Jewish) wants to eat it, she must wait after Shabbat however long it would take to make that roast. Our mishnah deals with a case where we don't know whether the work that was done on Shabbat was done for Jews or non-Jews. We should note that it doesn't matter who did the work Jew or non-Jew. What matters is whether the work was done for a Jew or for a non-Jew. This mishnah begins a series of mishnayot, all of which deal with a city in which there are some Jewish and some non-Jewish inhabitants.

אם יש בה רשות – the kingdom is called the authority/power (i.e., usually, it refers to the Roman government in Mishnaic times in the Land of Israel), because the license/permission/power is in its hand to do according to its will. But not specifically a king, but if there was there an important man, who has ten servants that warm up for him ten kettles of water at one time, it is permissible to wash in it immediately, and even though the majority of the city is Israelite. For we say, for the sake of that important person [the waters] were warmed up.

A city in which Israelites and non-Jews dwell together and there was a bathhouse working on Shabbat: In this city there is a bathhouse that operates on Shabbat and the question is whether a Jew can go and bathe there immediately after Shabbat in water that was heated on Shabbat.

If the majority [of the inhabitants] were non-Jews, one may bathe in it immediately [after the conclusion of the Shabbat]; If the majority were Israelites, one must wait until the water can be heated; If they were half and half, one must [also] wait until the water can be heated. If the majority of the residents of the city were non-Jews, then we can assume the water was heated on behalf of a non-Jew and one can bathe there right after Shabbat. If the majority were Jews then the water was probably heated for a Jew. In such a situation if the Jew bathed there immediately after Shabbat he would be deriving benefit from work done for a Jew on Shabbat. Therefore, he must wait a sufficient time after Shabbat for the water to have been heated. Then he can take a bath (always nice to take a bath after Shabbat). Again, if the amount of Jews and non-Jews is equivalent, the rule is strict.

Rabbi Judah says: if the bathhouse was small and there was there a [non-Jewish] authority, one may bathe in it immediately [after the conclusion of Shabbat]. If there was a small bathhouse and there was a non-Jewish, probably Roman, government located there, we can assume the water was heated for them (it's good to be the king, or the king's messengers). In this case a Jew could bathe there immediately after Shabbat, even if the majority of the city were Jews.

היה בה ירק, נמכר -vegetable that was detached on the Sabbath, is sold on Saturday night.

Introduction Our mishnah is a continuation of yesterday's mishnah, dealing with a city in which Jews and Gentiles live mixed.

אם רוב נכרים לוקח מיד – for since that the majority [of people] are heathens, I was detached with the knowledge of the heathens.

If one found in that city vegetables sold [on Shabbat]: The person finds vegetables in such a city and doesn't know whether they were picked that day and transported by a Jew or by a non-Jew. If they were picked by a Jew then they are prohibited because it is prohibited for a Jew to pick vegetables on Shabbat.

כדי שיבואו ממקום קרוב- where there are vegetables there. But even though that perhaps it was brought from a far-off place, one does not need to wait other than in order that they can harvest vegetables from a nearby place that has vegetables, and bring it from there. For the Sages did not say to wait until evening in order that it be done, but rather as a decree lest [a Jew] say to a heathen on the Sabbath: “Go and bring [vegetables],” and when he sees that he has to wait until evening in order that this thing will come, even from a nearby place, he should not say to a heathen to bring it to him on the Sabbath.

If the majority [of the inhabitants] were non-Jews, one may buy them immediately [after the conclusion of Shabbat]; If the majority were Israelites, one must wait until [vegetables] can arrive from the nearest place; If they were half and half, one must [also] wait until [vegetables] can arrive from the nearest place; This is the same as the clauses found in yesterday's mishnah.

ואם יש שם רשות לוקח מיד – that it is with the knowledge of an important person that they regularly always bring, and not with the knowledge of the Israelite that they brought it.

If there was there a [non-Jewish] authority, one may buy them immediately [after the conclusion of Shabbat]. As in yesterday's mishnah, we learn here that if there are some non-Jewish authorities in town we can assume that the special resources (vegetables, warm bath water) were designated for them. In this case, the Jew can buy the vegetables immediately after Shabbat.

אם רוב נכרים – and it is permitted to feed him (i.e., the baby) un-slaughtered carrion and torn animal flesh, forbidden animals and reptiles by hand (see Talmud Ketubot 15b).

If one found [an abandoned] child there: The mishnah continues to deal with a city composed of both non-Jews and Jews. A child is found, abandoned by his parents and we need to know whether to assume that the child is Jewish or not.

ואם רוב ישראל ישראל – and it incumbent [upon them] to restore to him his lost object like an Israelite. And by that change of expression (i.e., that the majority were Israelites), it was intended to add something new and unexpected here that we remove money from the hand of an Israelite that took possession of it, but we don’t say, establish that the money is in his possession from presumption that he had taken possession of it until he provides proof how that he is an Israelite.

If the majority [of the inhabitants] were non-Jews, it is considered a non-Jew; If the majority were non-Jews then in certain ways the child is treated as if s/he were non-Jewish. According to mishnaic commentaries based on the Talmud, we treat the child as non-Jewish and we are allowed to feed him/her non-kosher food.

מחצה על מחצה ישראל – regarding matters of damages, that if his ox gored the ox of an Israelites, he pays only one-half damages. But he does not pay full damages according to the law that an ox belonging to a heathen that gored the ox of an Israelite, that whether it is an innocent [ox]/תם or a warned/מועד [ox], it pays full damages, for he could say to him: “Bring proof that I am not an Israelite and pays. But to the remainder of all things here is doubt, and we judge him stringently. Whomever killed him, is not killed for him. If he betrothed a woman, she requires a Jewish bill of divorce from doubt. But he is not like a complete Israelite until he ritually immerses for the sake of conversion.

If the majority were Israelites, it is considered an Israelite; If the majority were Israelites, the child is treated like a Jew. According to commentaries this means that we are obligated to return lost objects to the child (when s/he grows up and owns things), which as we learned in Bava Metzia and we will see again in tomorrow's mishnah, is obligatory only to fellow Jews.

אחרי רוב המשליכין – that is after the heathens and even though they are the minority. And even if there was only one heathen woman there, she is suspected of those who abandon. But the Halakha is not according to Rabbi Yehuda.

If the majority were Israelites, it is considered an Israelite; If the town is evenly split, the child is considered Jewish. Again, the commentators limit this to a case of damages. If this child's ox damages a fellow Jew's ox, the child's ox only pays half damages, if it is an attested danger. Note that the ramifications of the child being considered Jewish were limited to monetary matters. The Talmud says that when it comes to matters of personal status, such as marital law, the child is considered to be a "doubtful Jew." If he marries a Jewish woman, she is potentially married and would require a divorce document to marry someone else. He/she is not fully considered an Israelite until conversion.

If they were half and half, it is also considered an Israelite. Rabbi Judah says that it is not logical to simply follow the majority of people in the city. We need to look at who most likely abandoned their kids. So if the majority of abandoners are Jews, then the kid is considered a Jew, even if the majority of the town is non-Jews.

רוב נחתומים – if most of the bakers are heathen, the bread is forbidden, for the bread of heathens is from the eighteen matters that they decreed on that day [that Rabban Gamaliel was deposed as head of the Sanhedrin] (see Tractate Shabbat, Chapter 1, Mishnah 4 and the Bartenura commentary there].

If one found there lost property, The issue here is finding lost property. The rabbis obligated one to declare lost property that was found and return it to the owner if the owner could identify it. These halakhot are found in the second chapter of Bava Metzia. This obligation is only to a fellow Jew. One is not obligated to return property to a non-Jew, at least not according to the Mishnah. Later halakhah rectified this discrimination, as it did in many cases.

פת עיסה – clean/white bread.

If the majority [of the inhabitants] were non-Jews, he need not proclaim it; If the majority was not Jewish, then he need not proclaim that he found a lost object because he can assume that it belonged to a non-Jew.

פת קיבר (eaters of black bread) – bread that is not pure/white.

If the majority were Israelites, he must proclaim it; If the majority were Jews he must proclaim it and if a Jew claims it, he would have to return it to him. This would make for quite an awkward situation if he proclaimed it and then it turned out to belong to a non-Jew.

אחר רוב אוכלי פת קיבר – if the majority of them are heathens, the bread is forbidden. Alternatively, one can explain: after the majority of the bakers, after the majority of those who eat white bread, etc. If the majority of them are members of the order for the observance of the Levitical laws in daily intercourse, the bread is ritually pure and there is no need to tithe. But if the majority are those not observing certain religious customs regarding tithes and Levitical cleanness, the bread is ritually impure and one needs to tithe.

If they were half and half, he must [also] proclaim it. If the split is 50/50 he must assume that it could belong to a Jew and he must proclaim it.

If one found bread there we must consider who form the majority of the bakers. The second half of the mishnah deals with bread that is found in the mixed city. The rabbis prohibited Jews from eating bread made by Gentiles, not because the bread is impure or not kosher, but in order to prevent assimilation. The first criterion is to follow the majority of bakers, as has been the rule in most of the previous mishnayot.

If it was bread of clean flour, we must consider who form the majority of those who eat bread of pure flour. However, if the bread is of a special kind, such as bread made of clean flour, we need to look at who makes clean flour bread. This is more expensive so it will be made probably by the upper class.

Rabbi Judah says: if it was coarse bread, we must consider who form the majority of those who eat coarse bread. Today coarse bread is the most expensive type of bread, but back then (and probably not too long ago), it was for the poorer folk. So Rabbi Judah adds that if the bread is of poor quality, i.e. it is coarse, then we can assume it was made by someone poor and we follow the majority of poor people.

הולכין אחר רוב טבחין – if the majority are Israelite butchers, the meat is permitted. For the Halakha is not according to Rav who stated that meat that was concealed from the eye is prohibited. But Rav establishes our Mishnah with regard to a case where a person stands and sees from the time that it (i.e., the meat) is slaughtered until it fell, but he did not know who slaughtered it.

If one found meat there, we follow the majority of the butchers. A piece of meat is found lying somewhere in this mixed city. Today, most of us would not really consider eating a piece of meat just found lying around, even those of us who don't keep kosher. But back then meat was exceedingly rare and if it looked good enough to eat, why not. The mishnah says that if the majority of butchers slaughter their meat in a kosher manner, then a Jew can eat the meat. Note that the meat is assumed to come from a butcher because normal people did not store meat in their homes. So we don't need to know who were the majority of the people.

If it was cooked meat, we follow the majority of those who eat cooked meat. I find this section very interesting. At first sight, one might wonder who doesn't eat cooked meat? Do some people eat raw meat? However, when we think about it, the mishnah shows us something interesting about meat consumption in those days. Most people probably didn't eat meat at all. Only wealthy people would be considered "those who eat cooked meat." So to figure out from whom the meat likely fell, we must consider who composes the majority of the wealthy people who eat cooked meat.

אם רוב מכניסין לבתיהן פטור - from tithing (see also Tractate Maaserot, Chapter 1, Mishnah 5).

Introduction Today's mishnah deals with finding produce in the mixed city and determining whether it needs to be tithed or not. Produce that has not been tithed generally may not be eaten once it is brought into one's home. However, under certain circumstances one may eat it while on the road. Produce that might or might not have been tithed is called demai. We'll discuss some of these rules here but for a fuller exposition, look at the Introduction to Demai, as well as the Introduction to Maasrot.

למכור בשוק חייב – that the majority brings [produce] to sell in the marketplace, it is from the house they bring it, and it is already liable [for tithing]. Another explanation: If the majority [of people] bring it into their homes, they are exempt [from tithing] because they regularly tithe prior to bringing it into the house in order that they would be able to eat from them [other than a snack/incidental meal]. For after they brought them into the house, they have immediately become susceptible for tithing. Therefore, what falls from them on the path/road is exempt from tithing, because it is under the presumption of having been tithed, but when they bring them [into the marketplace] to sell, it is the manner to bring them in as eatables forbidden pending the separation of sacred gifts/טבל, because one is able to eat from them an incidental meal/snack, therefore, that which falls from them is not under the presumption of being tithed.

If one found produce on the road: If the majority [of the inhabitants] gathered produce into their homes, he is exempt [from tithes]; If [the majority gathered it] for selling in the market, he is liable [for tithes]; If they were half and half, the produce is demai. According to Maasrot 1:5 if a person was carrying produce to his home, he may eat of the produce untithed until he gets home. But if he was bringing it to market, it cannot be eaten untithed as long as the processing has been finished (which it assumedly has if it's being brought to the market). So what we need to determine here is whether the produce was being brought to market or being brought home. As with the other mishnayot, so too here we follow a majority. If the majority was bringing the produce to the market, then he must tithe what he found even if he is only eating of them in an extemporaneous fashion and not as part of a meal. In other words, we assume that this produce was being brought to market in which case all further eating is prohibited. If there is no majority, then the produce is deemed demai. He must tithe them even if he wants to eat them before he gets home.

אם רוב נכרים ודאי – Rabbi Meir, according to his reasoning, who holds that there is no acquisition [of land] for heathens in the Land of Israel to release them from tithing, and produce that grew in the fields of heathens are liable for tithing, for the heathen simply did not tithe, therefore, they are definitely eatables forbidden pending the separation of sacred gifts/טבל.

A granary into which both Israelites and non-Jews put their produce, If the majority were non-Jews, [the produce must be considered] certainly untithed; If the majority were Israelites, [it must be considered] demai; If they were half and half, [it must be considered] certainly untithed, the words of Rabbi Meir. But the sages say: even if they were all non-Jews, and only one Israelite put his produce into the granary, [it must be considered] demai. There is a granary full of grain and we need to know whether it has been tithed or not. If the majority are non-Jews then we can be sure it has not been tithed. A Jew who eats such grain must certainly tithe it. If the majority are Israelites, then it might have been tithed. We can't know for sure because some Jews, perhaps many Jews, do not tithe. Therefore it is demai, which means that one must take out terumah, terumat maaser (the terumah taken from tithes) and maaser sheni. These must be removed because an Israelite cannot eat them. However, he does not have to take out first tithe or poor tithe, because these can be eaten by an Israelite (see Intro to Demai). If the numbers are evenly split, then Rabbi Meir assumes that it certainly hasn't been tithed. The sages disagree with Rabbi Meir and hold that even if only one Jew puts grain into the granary, all of the grain must be considered demai and not certainly untithed produce. The sages hold that grain grown on land owned by non-Jews is not liable for tithes. If the granary was only non-Jewish grain, he wouldn't be obligated to tithe it at all. However, since one Jew puts his grain in there he must treat it as demai, because the sages hold that Jewish grain is not annulled in a greater quantity of non-Jewish grain.

ואם רוב ישראל דמאי – according to the law of produce that is found in the hands of commoners [who are generally observing certain customs regarding tithes and Levitical uncleanness], that one needs to separate from them the tithe of the tithe (i.e., the tithe that the Levite gives to the Kohen) and the Second Tithe.

וחכמים אומרים וכו' – the Sages hold that there is acquisition [of land] for heathens in the Land of Israel to release them from tithing. But there wasn’t an Israelite who would put [his produce] into it (i.e., the storage bin). Everything is doubtfully tithed, for the produce of that Israelite, for they (i.e., the produce) is liable [for tithing]. And the Halakha is according to the Sages.

פירות שניה שרבו על של שלישית – The first year and second [year] of the Sabbatical cycle one [has the] practice [of giving] First Tithe and Second Tithe on them, and similarly in the fourth and fifth [years]. But in the third and sixth [years], [one gives] First Tithe and the Poor Man’s Tithe.

Introduction During the first, second, fourth and fifth years of the sabbatical cycle second tithe is taken out from produce. This tithe must be consumed in Jerusalem, or at least exchanged for money and separated in Jerusalem. In the third and sixth years the poor tithe is taken out and given to the poor. Seventh year produce is holy and it is forbidden to conduct business with it (i.e. sell it for a profit). Our mishnah deals with produce from the second year which are mixed with third year produce or other such mixtures. Makhshirin If the produce of the second year exceeded in quantity the produce of the third year, or the produce of the third year exceeded the produce of the fourth year, or the produce of the fourth year exceeded the produce of the fifth year, or the produce of the fifth year exceeded the produce of the sixth year, or the produce of the sixth year exceeded the produce of the seventh year, or the produce of the seventh year exceeded the produce of the year after the conclusion of the seventh year, we follow the majority. If half and half, the rule is stringent.

ושל שביעית – which has In it the sanctity of the Seventh Year and one is exempt from the tithe. And in regard the matter of all of these laws, it is taught that one follows after the majority.

The rule here is quite simple we follow the majority of the produce. Note that some of these possibilities are not really important, since the produce of those two years has the same status. For instance, if fourth and fifth year produce are mixed up, it doesn't matter because one takes second tithe from both. The mishnah just runs through the whole list of possibilities.

מחצה למחצה להחמיר – But in regard to a doubt of Second Tithe and the Poor Man’s Tithe, he should separate out one tithe, and profane the produce over the money, and separate the divide up the produce among the poor and consume the monies [of Second Tithe] in Jerusalem. But in regard to doubt regarding Seventh Year produce, they are liable for tithes and liable for the Holiness of the Seventh Year [produce] to not use them for business or for puffed up cheeks, and they are liable for removal of tithes (see Deuteronomy 26:13).

If the mixture is evenly split, we follow the strictest possibility. So if we are not sure if second tithe or poor tithe should be taken out he would have to take out both, and bring the second tithe to Jerusalem (or redeem it for money) and give the poor tithe to the poor. If there is a possibility that the produce is sabbatical year produce, then it all must be treated with the appropriate sanctity and one could not engage in business with it.