משנה: הַכֶּסֶף קוֹנֶה אֶת הַזָּהָב וְהַזָּהָב אֵינוֹ קוֹנֶה אֶת הַכֶּסֶף. הַנְּחוֹשֶׁת קוֹנֶה אֶת הַכֶּסֶף וְהַכֶּסֶף אֵינוֹ קוֹנֶה אֶת הַנְּחוֹשֶׁת. מָעוֹת הָרָעוֹת קוֹנוֹת אֶת הַיָּפוֹת וְהַיָּפוֹת אֵינָן קוֹנוֹת אֶת הָרָעוֹת. אֲסֵימָן קוֹנֶה אֶת הַמַּטְבֵּעַ וְהַמַּטְבֵּעַ אֵינוֹ קוֹנֶה אֶת אֲסֵימָן. הַמִּיטַּלְטְלִין קוֹנִין אֶת הַמַּטְבֵּעַ וְהַמַּטְבֵּעַ אֵינוֹ קוֹנֶה אֶת הַמִּיטַּלְטְלִין. זֶה הַכְּלָל. כָּל־הַמִּיטַּלְטְלִין קוֹנִין זֶה אֶת זֶה. MISHNAH: ¹A general reference to this Mishnah and the first paragraph of the Halakhah is in D. Sperber, Roman Palestine 200–400, Money and Prices, Ramat Gan 1974; Chapters XI,XIV. Silver acquires gold but gold does not acquire silver²It is accepted in rabbinic law (in the name of R. Yannai in Bava Metzia 4:2:2-7" href="/Jerusalem_Talmud_Bava_Metzia.4.2.2-7">Halakhah 4:2, in the Babli 46b in the name of R. Joḥanan) that in Biblical law money acquires both ownership and possession though this is denied in the other Yerushalmi Tractates in the name of R. Joḥanan, (Sheviit 8:1:4" href="/Jerusalem_Talmud_Sheviit.8.1.4">Ševi‘it 8:1 Note 15, Erubin7:11 24d l. 3). But it is universally accepted that in rabbinic practice payment only establishes a claim to ownership and possession, not a fact. This is to avoid fraudulent transactions in which the seller sells non-existent goods and then claims that they were lost, e. g., by fire, between sale and delivery when they already were owned by the buyer but not yet in his possession. On the other hand, in a barter transaction taking possession by one party automatically transfers both ownership and possession to the other party (Kiddushin 1:6:2-6" href="/Jerusalem_Talmud_Kiddushin.1.6.2-6">Qiddušin 1:6). If a person loses because the other party who took money in a commercial transaction then refuses to go through with the sale and offers to refund the money, he can ask the court to publicly curse the defaulting party but he has no legal way to force completion of the sale (Bava Metzia 4:2:1" href="/Jerusalem_Talmud_Bava_Metzia.4.2.1">Mishnah 2). But if the buyer took possession of the merchandise, then the sale is completed; the seller can force payment in court and is not required to take the article back. This means that transactions involving money are considered a kind of barter in which coins always are passive but never active objects of barter.
There is no doubt that gold or silver bars are merchandise, objects of trade and barter. The question is about coins. If gold coins are exchanged for silver coins and vice-versa, the question is which of the species are considered as merchandise and which as coins in the transaction. The Babli and all sources depending on it (Mishnah and Tosephta mss.) state that “Gold acquires silver but silver does not acquire gold,” the opposite of the Yerushalmi. The Halakhah states that originally, the Yerushalmi Mishnah was identical with the Babli; the change can be dated to the early Third Century.
D. Sperber has argued convincingly that this is not a question of gold or silver standard since both the Roman and the Parthian, later Persian, empires actually were on a gold-and-silver standard. But the Persian empire never experienced the disastrous manipulation of silver coinage which started with Caracalla and ended with the hyper-inflation of the military anarchy, only to be brought under control by Diocletian’s currency reform. By contrast, even the worst Roman emperors did not adulterate gold coinage (if they minted gold at all.) Therefore, in Babylonia silver coin was the common vehicle of trade while gold coin was used only in very large transactions or as a vehicle for hoarding. This means that silver coin was “money” but gold coin was “merchandise” even when gold coin did not trade at an agio over the official ratio. But in the Roman empire in the period of formulation of the Mishnah (roughly 190–230) silver coins changed from dependable vehicle of commerce to objects to be disposed of as quickly as possible; silver became a merchandise relative to gold coin.. Brass acquires silver but silver does not acquire brass³In good times, brass coins are local currency only which cannot be used at far-away places; they are tokens rather than coins. When tokens are exchanged for coins, the tokens are the merchandise. In bad times, when “silver” coins were brass coins slightly washed in a silver solution, brass coins did not exist.. Bad coins⁴Coins taken out of circulation; they are not money in the legal sense. acquire good ones but good ones do not acquire bad ones. A blank⁵Metal disks ready to be stamped in the mint. They are not money until stamped. acquires a coin but a coin does not acquire a blank. Movables acquire coins but coins do not acquire movables²It is accepted in rabbinic law (in the name of R. Yannai in Bava Metzia 4:2:2-7" href="/Jerusalem_Talmud_Bava_Metzia.4.2.2-7">Halakhah 4:2, in the Babli 46b in the name of R. Joḥanan) that in Biblical law money acquires both ownership and possession though this is denied in the other Yerushalmi Tractates in the name of R. Joḥanan, (Sheviit 8:1:4" href="/Jerusalem_Talmud_Sheviit.8.1.4">Ševi‘it 8:1 Note 15, Erubin7:11 24d l. 3). But it is universally accepted that in rabbinic practice payment only establishes a claim to ownership and possession, not a fact. This is to avoid fraudulent transactions in which the seller sells non-existent goods and then claims that they were lost, e. g., by fire, between sale and delivery when they already were owned by the buyer but not yet in his possession. On the other hand, in a barter transaction taking possession by one party automatically transfers both ownership and possession to the other party (Kiddushin 1:6:2-6" href="/Jerusalem_Talmud_Kiddushin.1.6.2-6">Qiddušin 1:6). If a person loses because the other party who took money in a commercial transaction then refuses to go through with the sale and offers to refund the money, he can ask the court to publicly curse the defaulting party but he has no legal way to force completion of the sale (Bava Metzia 4:2:1" href="/Jerusalem_Talmud_Bava_Metzia.4.2.1">Mishnah 2). But if the buyer took possession of the merchandise, then the sale is completed; the seller can force payment in court and is not required to take the article back. This means that transactions involving money are considered a kind of barter in which coins always are passive but never active objects of barter.
There is no doubt that gold or silver bars are merchandise, objects of trade and barter. The question is about coins. If gold coins are exchanged for silver coins and vice-versa, the question is which of the species are considered as merchandise and which as coins in the transaction. The Babli and all sources depending on it (Mishnah and Tosephta mss.) state that “Gold acquires silver but silver does not acquire gold,” the opposite of the Yerushalmi. The Halakhah states that originally, the Yerushalmi Mishnah was identical with the Babli; the change can be dated to the early Third Century.
D. Sperber has argued convincingly that this is not a question of gold or silver standard since both the Roman and the Parthian, later Persian, empires actually were on a gold-and-silver standard. But the Persian empire never experienced the disastrous manipulation of silver coinage which started with Caracalla and ended with the hyper-inflation of the military anarchy, only to be brought under control by Diocletian’s currency reform. By contrast, even the worst Roman emperors did not adulterate gold coinage (if they minted gold at all.) Therefore, in Babylonia silver coin was the common vehicle of trade while gold coin was used only in very large transactions or as a vehicle for hoarding. This means that silver coin was “money” but gold coin was “merchandise” even when gold coin did not trade at an agio over the official ratio. But in the Roman empire in the period of formulation of the Mishnah (roughly 190–230) silver coins changed from dependable vehicle of commerce to objects to be disposed of as quickly as possible; silver became a merchandise relative to gold coin.. This is the rule: all movables acquire one another⁶Kiddushin 1:6:1" href="/Jerusalem_Talmud_Kiddushin.1.6.1">Mishnah Qiddušin 1:6..

הלכה: הַכֶּסֶף קוֹנֶה אֶת הַזָּהָב כול׳. זֶהוּ כְּלָלוֹ שֶׁלְּדָבָר. כָּל־הַיָּרוּד מֵחֲבֵירוֹ קוֹנֶה אֶת חֲבֵירוֹ. אָמַר רִבִּי חִייָה בַּר אַשִּׁי. מָאן תַּנִּיתָהּ. רִבִּי שִׁמְעוֹן בֵּרִבִּי. אָמַר לֵיהּ אָבוֹי. חֲזוֹר בָּךְ וְתַנִּי כְהָדָא. הַזָּהָב קוֹנֶה אֶת הַכֶּסֶף. אָמַר לֵיהּ. לֵינָא חָזַר בִּי. דְּעַד דַּהֲוָה חֵילָךְ עָלַיִךְ אַתְנִיתָנִי. הַכֶּסֶף קוֹנֶה אֶת הַזָּהָב. מִילְּתֵיהּ דְּרִבִּי אָֽמְרָה. זָהָב כְּפֵירוֹת. מַתְנִיתָא אָֽמְרָה. כֶּסֶף כְּפֵירוֹת. [מַתְנִיתָה דְּרִבִּי חִייָה אָֽמְרָה. זָהָב כְּפֵירוֹת. מִלְּתֵיהּ אָֽמְרָה. כֶּסֶף כְּפֵירוֹת. כְּהָדָה] בְּרַת רִבִּי חִייָה רוֹבָה אוֹזְפָת לְרַב דֵּינָרִין. אֲתַת שְׁאָלַת לָאֲבוּהּ. אֲמַר לָהּ. שְׁקִילִי מִינֵּיהּ דֵּינָרִין טָבִין וּתְקִילִין. מִבְּרַת רִבִּי חִייָה יָֽלְפִין. אָמַר רִבִּי אִידִּי. אוֹף אַבָּה אֲבוֹי דִשְׁמוּאֵל בְּעָא קוֹמֵי רִבִּי. מָהוּ לִלְווֹת דֵּינָרִין בְּדֵינָרִין. אָמַר לֵיהּ. מוּתָּר. אָמַר רִבִּי יַעֲקֹב בַּר אָחָא. אוֹף רִבִּי יוֹחָנָן וְרֵישׁ לָקִישׁ תְּרֵיהוֹן מָרִין. מוּתָּר לִלְווֹת דֵּינָרִין בְּדֵינָרִין. קָרַט בְּקָרַט שָׁרֵי. לֵקָן בְּלֵקָן אָסוּר. HALAKHAH: “Silver acquires gold,” etc. This is a summary of the matter: Anything worth less that the other acquires the other. Rebbi Ḥiyya bar Ashi said, who stated this? Rebbi Simeon ben Rebbi⁷Babli 44a.. His father told him, change your opinion and state the following: “Gold acquires silver.⁸The version accepted in Babylonia sees the world as it should be; not the temporary state at the beginning military anarchy in the Roman empire when the currency was manipulated.” He told him, I do not change my opinion since when your faculties were unimpaired, you instructed me to state: “Silver acquires gold.” The word of Rebbi implies that gold is like produce⁹It has the power of merchandise to transfer possession and finalize a deal.. The Mishnah implies that silver is like produce⁹It has the power of merchandise to transfer possession and finalize a deal.. [Rebbi Ḥiyya’s baraita implies that gold is like produce¹⁰Tosephta 3:13., but his word implies that silver is like produce, as in the following:]¹¹Addition of E. The characterization of the Tosephta as Galilean might raise doubts as to the genuineness of the addition. The elder Rebbi Ḥiyya’s daughter lent denars¹²Gold denars. to Rav. She came and asked her father, who told her: Take from him good and full weight denars¹³Babli 44b. The problem here is the prohibition of taking interest, which is defined as “payment for waiting” (Babli 65a). Therefore, it is forbidden to lend merchandise on condition to receive the same amount of merchandise in return at a specified future time since in the meantime the value of the merchandise might have increased and the lender would be repaid more in monetary value than what he lent out. It is required to determine the monetary value of the articles to be lent before they are transferred. The only exceptions are (a) short term loans and (b) bridge loans where the borrower already owns the borrowed items while they are stored at another locality. If R. Ḥiyya holds that silver is merchandise, how can he allow his daughter to lend gold coin against gold coin? The Babli explicitly states that during the term of the loan, gold rose in price against silver.. Do we learn from Rebbi Ḥiyya’s daughter¹⁴The story is irrelevant for the problem of this Halakhah since Rav states in Bava Metzia 5:5:8" href="/Jerusalem_Talmud_Bava_Metzia.5.5.8">Halakhah 5:7 (Note 135) that between close relatives the taking of interest is permitted. Rav was the student of his uncle R. Ḥiyya until he returned to Babylonia in 218; he was R. Ḥiyya’s daughter’s cousin. All we can learn is that Rav’s statement is really R. Ḥiyya’s. [S. Abramson in Sinai 89 (1981) pp. 217–218.] It is not stated whether the lender was Pazi or Martha.? Rebbi Idi said, also Abba, Samuel’s father, asked before Rebbi: May one lend denars against denars¹²Gold denars.? He answered him, it is permitted¹⁵The answer of a young R. Jehudah ben Rabban Simeon.. Rebbi Jacob bar Aḥa said, also Rebbi Joḥanan and Rebbi Simeon ben Laqish both instruct: It is permitted to lend denars against denars. Qerat against qerat is permitted, lekan against lekan is forbidden¹⁶Sperber’s analysis (l. c. pp. 92–93) makes it probable that the last sentence is not R. Joḥanan’s and R. Simeon ben Laqish’s, but is the editor’s deduction from the preceding statement. He notes that qeraṭ can either be the Greek κεράτιον, a gold weight, 1/1728 libra aurei, in Dioclation’s system equal in value with the silver siliqua, 1/24 solidus, or Syriac קרטא, quarta(pars sicli), one denar. Since we are dealing with coins, the preferred meaning is that of siliqua, an honest silver coin which did not exist during R. Joḥanan’s lifetime. Lekan was proposed in Ma‘aśer Šeni 4:1, Note 22, as “small measure or weight”, i. e. local small change which in the Mishnah had been defined as merchandise when compared with silver. {The computation of R. Eliahu Fulda in Ma‘aśer Šeni 4:1, who wanted to prove that the lekan was 1/62.5 of a solidus, was already shown to be in error by H. Y. Sheftel [Encyclopedia of biblical and rabbinic coins, measures, weights, areas, and time, Berdiczew 1907 (Hebrew)]}..

תַּמָּן תַּנִּינָן. כָּל־הַנַּעֲשֶׂה דָּמִים בְּאַחֵר כֵּיוָן שֶׁזָּכָה זֶה נִתְחַייַב בַּחֲלִיפָיו. אָמַר רִבִּי יוֹחָנָן לֹא שָׁנוּ אֶלָּא שׁוֹר בְּפָרָה אוֹ חֲמוֹר בְּשׁוֹר. הָא צִיבּוּר בְּצִיבּוּר לֹא קָנָה. רַב יִרְמְיָה בְשֵׁם רַב. אֲפִילוּ צִבּוּר בְּצִיבּוּר קָנָה. רִבִּי אַבָּא בַּר מִינָה בְשֵׁם רַב. הַמַחֲלִיף אברוקלון בְּאמבורוקלון קָנָה. There, we have stated: If anything is given instead of money, if one entered in possession, the other is obligated for its exchange¹⁷Cf. Note 2, Kiddushin 1:6:1" href="/Jerusalem_Talmud_Kiddushin.1.6.1">Qiddušin 1:6, Note 521.. Rebbi Joḥanan said, they stated this only about an ox for a cow, or a donkey for an ox; but heap against heap one did not acquire. Rav Jeremiah in the name of Rav: Even heaps among heaps he did acquire¹⁸Kiddushin 1:6:2" href="/Jerusalem_Talmud_Kiddushin.1.6.2">Qiddušin 1:6, Note 525. If one of the parties took possession, the other party automatically obtained possession of the exchanged property.. Rebbi Abba bar Mina in the name of Rav: One who exchanged אברוקלון against אמברוקלון did acquire¹⁹The reading of R. Ḥananel and ‘Arukh is: One who exchanged אמבורקלין against אמבורקלין did acquire. Arukh explains as “bundles of sheets” which in Italian (dialect of Rome) would be called ברוקלי (variants ברוקלון, ברוקלו) or (תרצילו, טורצלי, תרוצולו, תורצלו) .טרצילו. The second word is identified by Krauss in Additamenta ad librum Aruch Completum as turzello. M. Sachs (J. Levy, S. Krauss) identifies אמבורוקלון as Latin involucrum “wrapper; covering; envelope”, from involvo “to wrap up, roll up.”. Turzello, from Latin tortus “a twisting, winding”, from torqueo “to twist, to turn” is an acceptable translation of involucrum. In this interpretation, the statement implies that the laws of barter also apply if something is exchanged against an object of the same kind. It is difficult to understand why this should not be so.
H. Y. D. Azulay, in his פתח עיניים, quotes from the ms. of R. Menaḥem di Lonzano בדיקלין באמה בדיקלין. E: אמלוקנין באמבוליקין.
However, Maimonides connects the statement with the later Mishnaiot whose subject is the cancellation of a sale because of overcharging by the seller or underpaying by the buyer. He reads the statement as meaning that a barter is concluded the moment one of the parties takes possession of the object coming to him, and no legal recourse exists for the party realizing that he made a bad bargain. He must hold that אברוקלון and אמבורוקלון are two different objects. It is possible that he reads the two words as “needle” and “silk cloth” since he writes (Mekhirah 13:1): “One who barters vessels agains vessels or animals against animals, even a needle for silk cloth or a kid goat for a horse, has no claim of overcharging since he might prefer a needle to silk cloth.” The horse is specifically exempt from the rules of overcharging in Halakhah 4, Note 132. (Ravad objects and thinks that Maimonides misunderstood the Yerushalmi.) The commentary Migdal ‘Oz (R. Šem-Ṭob Gabbai) readsאמבורקלין אמטרקלין, but gives no explanation of the words beyond noting that these clearly denote different objects..

רִבִּי זֵירָא רַב יְהוּדָה בְשֵׁם שְׁמוּאֵל. לָזֶה פָרָה וְלָזֶה חֲמוֹר וְהֶחֱלִיפוּ זֶה בָּזֶה. וּמָשַׁךְ בַּעַל הַחֲמוֹר אֶת הַפָּרָה וּבָא בַּעַל הַפָּרָה לִמְשׁוֹךְ הַחֲמוֹר וּמְצָאָהּ שְׁבוּרָה. בַּעַל הַחֲמוֹר עָלָיו לְהָבִיא הָרְאָייָה שֶׁהָֽיָה הַחֲמוֹר שָׁלֵם בְּשָׁעָה שֶׁמָּשַׁךְ. מָאן דְלָא סְבַר הָא מִילְּתָא לָא סְבַר בִּנְזָקִין כְּלוּם. אָמַר רִבִּי זֵירָא. לֵינָה סְבַר הָדָא מִילְּתָא וְלֵינָה סְבַר בִּנְזָקִין כְּלוּם. תַּמָּן תַּנִּינָן. הָיוּ בָהּ מוּמִין וְעוֹדָהּ בְּבֵית אָבִיהָ כול׳. רִבִּי חוּנָא רִבִּי פִּינְחָס רִבִּי חִזְקִיָּה סָֽלְקוֹן גַּבֵּי רִבִּי יוֹסֵי לְגַדְּפָה. אָֽמְרִין קוֹמוֹי הָדָא וְאָמַר לוֹן. אֱמוֹר דְּבַתְרָהּ. נִכְנְסָה לִרְשׁוּת הַבַּעַל הַבַּעַל צָרִיךְ לְהָבִיא רְאָייָה. וְלֹא הָאָב שֶׁהוּא צָרִיךְ לְהָבִיא רְאָייָה. וְתֵימַר הַבַּעַל צָרִיךְ לְהָבִיא רְאָייָה. אוֹף הָכָא הַבַּעַל צָרִיךְ לְהָבִיא רְאָייָה. ²⁰This text is an outline of the detailed argument in Kiddushin 1:6:3" href="/Jerusalem_Talmud_Kiddushin.1.6.3">Qiddušin 1:6, Notes 532–542. Rebbi Ze‘ira²¹In Qiddušin, R. Abba. Since R. Ze‘ira objects to the statement in both texts, and the Qiddušin text is reproduced in the next paragraph, the attribution here is incorrect., Rav Jehudah in the name of Samuel: One had a cow and one a donkey. They exchanged one for the other. The donkey’s owner took the cow. When the cow’s owner came to take the donkey and found that it had a fracture, the donkey’s owner had to bring proof that his donkey was well at the moment he took the cow. Anybody who does not agree to this does not know anything about civil law. Rebbi Ze‘ira said, I do not agree, I do not know anything about civil law. There, we have stated²²Ketubot 7:7:1" href="/Jerusalem_Talmud_Ketubot.7.7.1">Mishnah Ketubot 7:9. After the definitive wedding, the husband discovers that his bride has a bodily defect and divorces her for that. He does not want to pay her ketubah. A prima facie argument is that the defect happened where it was discovered. Therefore, if the bride was still in her father’s house, the father has to prove that at the time of the preliminary wedding his daughter was without blemish. If the bride now is in her husband’s house, the husband has to prove that she was already blemished at the preliminary wedding when he agreed to be financially responsible for her. Similarly, the rule is that if the donkey was in his first owner’s stable when the buyer found it with a broken leg that the stable’s owner has to prove that it was healthy at the time he took possession of the cow.: “If she had bodily defects, as long as she was in her father’s house,” etc. Rebbi Ḥuna, Rebbi Phineas, and Rebbi Ḥizqiah went to visit Rebbi Yose to sharpen wits. They quoted the statement²²Ketubot 7:7:1" href="/Jerusalem_Talmud_Ketubot.7.7.1">Mishnah Ketubot 7:9. After the definitive wedding, the husband discovers that his bride has a bodily defect and divorces her for that. He does not want to pay her ketubah. A prima facie argument is that the defect happened where it was discovered. Therefore, if the bride was still in her father’s house, the father has to prove that at the time of the preliminary wedding his daughter was without blemish. If the bride now is in her husband’s house, the husband has to prove that she was already blemished at the preliminary wedding when he agreed to be financially responsible for her. Similarly, the rule is that if the donkey was in his first owner’s stable when the buyer found it with a broken leg that the stable’s owner has to prove that it was healthy at the time he took possession of the cow. and he told them, look at the next statement: “Once she entered the husband’s domain, the husband has to prove.” Would not the father have to prove? But you are saying that the husband has to prove; here also, the owner has to prove.

רִבִּי בָּא רַב יְהוּדָה בְשֵׁם שְׁמוּאֵל. לָזֶה פָרָה וְלָזֶה חֲמוֹר וְהֶחֱלִיפוּ. מָשַׁךְ בַּעַל הַחֲמוֹר אֶת הַפָּרָה לֹא קְנָאָהּ. חֲמוֹר מָהוּ שֶׁתִּקָּנֶה. רִבִּי בָּא אָמַר. קָנָה. רִבִּי יָסָא אָמַר. לֹא קָנָה. אָמַר רִבִּי מָנָא. אִית הָכָא מִילֵּי דְיוֹדֵי בָהּ רִבִּי יוֹסֵי. אָדָם שֶׁאָמַר לַחֲבֵירוֹ. פָּרָתִי אֲנִי מְבַקֵּשׁ לִמְכּוֹר. אָמַר לֵיהּ. בְּכַמָּה. אָמַר לֵיהּ. בְּח̇ דֵינָרִין. אֲזַל סָֽמְכֵיהּ גַּבֵּי טרפוניטיה. בְּצַפְרָא עֲבַר וְאַשְׁכְּחֵיהּ תַּמָּן קָאִים. אֲמַר לֵיהּ. מָה אַתְּ עֲבִיד הָכָא. אֲמַר לֵיהּ. אֲנָא בָּעִי מֵיסַב דֵּינָרִין דְּאַסְמִיכְתָּנִי. אֲמַר לֵיהּ. מָה אַתְּ בָּעֵי מִיזְבּוֹן לָךְ בְּהוֹן. אֲמַר לֵיהּ. חֲמוֹר. אֲמַר לֵיהּ. חֲמוֹרָךְ אֶצְלִי. מָשַׁךְ זֶה לֹא קָנָה זֶה מָשַׁךְ זֶה לֹא קָנָה זֶה. אֶלָּא כָּל־אֶחָד וְאֶחָד נִקְנֶה בְגוּפוֹ. ²³This paragraph is similar to one in Kiddushin 1:6:4" href="/Jerusalem_Talmud_Kiddushin.1.6.4">Qiddušin 1:6, Notes 543–549. The initial sentence is out of place in this paragraph; it should be the start of the preceding one, cf. Note 21. The missing starting sentence would indicate that the parties to a trade determined the monetary value of the animals traded. No money actually changed hands because they agreed that the prices of the items exchanged were equal. The question now arises whether the transaction has to be classified as sell-and-buy, in which case each party has to take possession by an act of acquisition, or as barter, when the taking of possession of one party automatically transfers possession also to the other party.(Rebbi Abba, Rav Jehudah in the name of Samuel: One had a cow and one a donkey. They exchanged them.) The donkey’s owner took the cow; he did not acquire it²⁴Obviously, this statement does not fit the preceding sentence; it refers to the statement of R. Abba, Rav Hamnuna, Rav Ada bar Aḥawa in the name of Rav (Kiddushin 1:6:2-6" href="/Jerusalem_Talmud_Kiddushin.1.6.2-6">Qiddušin 1:6, 60d l. 75, Note 543): A cow was originally sold for a fixed sum. Then the buyer had second thoughts and offered the seller a donkey instead of money. If now they exchange the animals, it is not barter. Since the first to take the other’s animal takes something for which he did not pay, and the sale was not a credit sale, he cannot have acquired the animal until the other party also takes his. The only problem left open is whether the second party also has to execute a conscious act of acquisition; this is required by R. Yose but waved by R. Abba.. Would the donkey be acquired? Rebbi Abba said, he acquired. Rebby Yasa said, he did not acquire. Rebbi Mana said, there is a situation in which Rebbi Yose would agree: A man said to another, I want to sell my cow. He asked him, for how much? He answered, for eight denars. He went and gave him a draft on his banker²⁵For the unexplained word טרפוניטיה, Migdal Oz (loc. cit. Note 19) reads טרפיזטא τραπεζίτης “banker”, the Greek equivalent of Mishnaic שׁוּלְחָנִי. In Qiddušin it simply says, “he gave him a draft for money, פריטייא”; the last term might refer to Greek πρατήριον, τό “place for selling, market” (E. G.). In the morning he went and found him open for business. He asked him, what are you doing here? He answered, I want to collect the denars in the draft I have on you. He asked him, what do you want to buy with them? He answered, a donkey. He told him, your donkey is with me. If either of them took possession, the other did not acquire but each animal separately has to be taken in possession²⁶Since three people are involved, the seller of the cow, the buyer of the cow, and the banker as seller of the donkey, this is a sale and a separate buy, not a barter. Two separate acts of acquisition are unquestionably required..