Open-source JudaismDouglas Rushkoff, who originated the term, consistently capitalized Open Source Judaism (see the citations in later sections). Open Source may be capitalized in recognition of the usage of The Open Source Definition as a trademark of the Open Source Initiative, although open source itself is not a trademark. When not referring specifically to Rushkoff's ideas, this article generally employs the lowercase, hyphenated form open-source Judaism, similar to the usual form for analogous movements such as open-source software and open-source religion. is a name given to initiatives within the Jewish community employing open content and open-source licensing strategies for collaboratively creating and sharing works about or inspired by Judaism. Open-source efforts in Judaism utilize licensing strategies by which contemporary products of Jewish culture under copyright may be adopted, adapted, and redistributed with credit and attribution to the creators of these works. Often collaborative, these efforts are comparable to those of other open-source religious initiatives inspired by the free culture movement to openly share and broadly disseminate seminal texts and techniques under the aegis of copyright law. Combined, these initiatives describe an open-source movement in Judaism that values correct attribution of sources, creative sharing in an intellectual commons, adaptable future-proof technologies, open technological standards, open access to primary and secondary sources and their translations, and personal autonomy in the study and craft of works of Torah.

Sharing Torah in Rabbinic Judaism

Unencumbered access to educational resources, the importance of attribution, and limiting proprietary claims on intellectual property, are all matters common to open-source, the free culture movement, and rabbinic Judaism. Open-source Judaism concerns itself with whether works of Jewish culture are shared in accord with Jewish teachings concerning proper stewardship of the Commons and civic responsibilities of property ownership.

The rhetorical virtue of parrhesia appears in Midrashic literature as a condition for the transmission of Torah. Connoting open and public communication, parrhesia appears in combination with the term, δῆμος (dimus, short for dimosia), translated coram publica, in the public eye, i.e. open to the publicA meaning found in Sylloge lnscriptionum Graecum, 2nd edition, ed. Diltenberger 1888-1901, no.807, an inscription from after 138 C. E. As a mode of communication it is repeatedly described in terms analogous to a Commons. Parrhesia is closely associated with an ownerless wilderness of primary mytho-geographic import, the Midbar Sinai in which the Torah was initially received. The dissemination of Torah thus depends on its teachers cultivating a nature which is as open, ownerless, and sharing as that wilderness.Bamidbar Rabbah 1:7 Here is the text from the Mekhilta where the term dimus parrhesia appears (see bolded text).

Torah was given over dimus parrhesia in a maqom hefker (a place belonging to no one). For had it been given in the Land of Israel, they would have had cause to say to the nations of the world, “you have no share in it.” ["it" being Torah] Thus was it given dimus parrhesia, in a place belonging to no one: “Let all who wish to receive it, come and receive it!” Why was the Torah not given in the land of Israel? In order that the peoples of the world should not have the excuse for saying: `Because it was given in Israel's land, therefore we have not accepted it. Another reason: To avoid causing dissension among the tribes [of Israel]. Else one might have said: In my land the Torah was given. And the other might have said: In my land the Torah was given. Therefore, the Torah was given in the Midbar (wilderness), dimus parrhesia, in a place belonging to no one. To three things the Torah is likened: to the Midbar (wilderness), to fire, and to water. This is to tell you that just as these three things are free to all who come into the world, so also are the words of the Torah free to all who come into the world..

Moreover, the place in which the story of the Torah's revelation occurred becomes analogous to the personal virtue that a student and teacher of Torah must cultivate in oneself. In the midrashic work, Bamidbar Rabbah (1:7), an exegesis based on the phonetic similarities between the name Sinai, and the word she'eino meaning "that is not," is offered:

"God spoke to Moshe in the Sinai wilderness" (Numbers 1:1). This teaches us that anyone that is not (she'eino) making themselves into a midbar hefker (a wilderness belonging to no one) cannot acquire Wisdom and Torah, and so it is called in the Sinai wilderness.

The question of whether ḥidushei torah (innovative teachings in torah), Jewish liturgy, and derivative and related work are in some sense proprietary is subordinate to the importance given to preserving the lineage of a teaching. According to a mishnaic teaching of Rabbi Yehoshua ben Levi, the 48th attribute of an excellent student is their capability in citing a teaching in the name of the one they learned it from.

The question of whether new works of Torah learning are given the status of property is a question born of the commodification of printed works, competition, and prestige in modernity. In their academic article "Is Copyright Property? – The Debate in Jewish Law," Neil Netanel and David Nimmer explain that, Rabbinic tradition recognizes a fundamental public interest in making ḥidushei torah freely available to a community in need of knowledge and guidance about how Jewish law applies to contemporary life. Partly for that reason, Jewish law has long prohibited rabbinic scholars from profiting from teaching Jewish law and religion.That prohibition has been narrowly applied to enable scholars to earn a livelihood from teaching and fulfilling other rabbinic functions. For further discussion, see Neil W. Netanel, Maharam of Padua v. Giustiniani: The Sixteenth-Century Origins of the Jewish Law of Copyright, 44 HOUS. L. REV. 821, 862 (2007). Some argue, accordingly, that authors of ḥidushei torah may not assert a right to profit from their sale. Others mitigate that rule by distinguishing between the intangible work, that is the actual teaching presented in the book or tape, on the one hand, and the author’s labor and investment in reducing his teaching to writing or other fixed form and in printing, reproducing, and distributing the copies of his work, on the other. The author may not profit from, and has no property right in, the teaching itself, but is entitled to receive the full, customary salary for his labor and investment in preparing the manuscript or recording and in producing and distributing copies."

According to rabbinic Jewish teaching, the primary sin committed by the people of Sodom was their insistence on the absolute primacy of property, declaring that "what is mine is mine and what is yours is yours."Mishna Avot 5:10, Pirkei Avot 5:13

As applied by rabbinic jurists, the rule against acting like a Sodomite gives rise to three possible limitations on copyright, even assuming that copyright is property. First, if an author has created and disseminated his work with no intention of profiting from it, he suffers no economic loss even if another benefits from his work without paying for it, and thus such an author might be acting like a Sodomite were he to insist upon payment after the fact.Cohen, Yaakov Avraham. Emeq Ha-Mishpat, Vol. 4: Zekhuyot Yotsrim [Valley Of The Law, Vol. 4: Copyright] (1999) (Hebrew) Second, the rule against Sodomite behavior supports the view of some rabbinic jurists that private copying is permitted so long as the copier would not have otherwise purchased the copy and thus causes the author no loss. Third, the rule might be the basis for limiting copyright’s duration for published works. In his seminal ruling rejecting a perpetual, proprietary copyright while conceding that authors have an exclusive right to print their unpublished manuscripts, [Rabbi] Yitzhak Schmelkes [1828-1905] reasoned that copying causes the author no damage (as distinct from foregone profit) once the first edition has been sold, and thus that the rule against Sodomite behavior negates any continuing claim the author might have to enforce an exclusive right to print following the first edition.Schmelkes, Yitzhak. Beit Yitzhak, Yoreh De’ah, Pt. 5, No. 75 (Pyzemsyl 1875) (Hebrew)

What is akin to copyright in Jewish law in part derives from exclusive printing privileges that rabbinic authorities have issued since the invention of the printing press and date back to 1518. These privileges typically give the publisher the exclusive right to print the book for a period of ten to twenty years or until the first edition has been sold (i.e., after the author or heirs have recovered their investment). According to the minority position of Rabbi Joseph Saul Nathanson (1808–1875), a copyright is itself a property right arising out of the right of ownership. However, according to the majority position of Rabbi Yitzhak Schmelkes, "the author’s exclusive right to publish a manuscript and sell a first edition flows not from a proprietary copyright in the text, but only from the Jewish law of unfair competition or from the author’s right to condition access and use of the physical chattel, the manuscript, in which the author holds a property right." Ultimately, determination on the legal treatment of works of Jewish liturgy and ḥidushei torah depend upon a basic facet of rabbinic Jewish law: dinah malkhuta dina—the law of the land is (accorded to the status of) the Law.Shilo, Shmuel. Dina De-Malkhuta Dina (Dfus Akademi 1974) (Hebrew). Under United States copyright law, for instance, all newly created "creative" works are considered as intellectual property and afforded proprietary property rights that restrict adaptation and redistribution of the works by others without explicit permission granted by the copyright owner.

To establish a community based instead on ḥesed (lovingkindness), the custom has long been for individuals to share or provide others with personal possessions as needed. The institution of the G'MaḤ provided a practical example for the sharing of books, tools, and services. The ideal of contributing to or forming one's own G'MaḤ was popularized by Rabbi Yisrael Meir Kagan (1838–1933), who addressed many halakhic questions about the practice and lauded the spiritual benefits of lending property in chapter 22 of his work, Ahavat Ḥesed (Loving Loving-kindness, 1888): "[Lending property] stems from compassion and constitutes a mitzvah, as ḤaZa"L have pointed out: "tzedaka is performed with one's money; ḥesed with one's money and one's self."Talmud Bavli Sukkah 49b Rashi explains ḥesed here to mean the lending of money, chattel (personal property), livestock—all being included in the mitzvah."

Free–libre and open-source software

Prior to the coinage and adoption of the term "Open Source" in 1998, several Jewish computer scientists, typographers, and linguists developed free software of interest to Jews, students of Judaism, and readers of Hebrew. "Free software" (not to be confused with freeware) is software shared under a free license (such as the GPL), where the definition of "free" is maintained by freedomdefined.org.

Much of the development of free and open-source software was developed by Israeli computer scientists and programmers for the display, analysis, and manipulation of Hebrew text. This development has been celebrated by Hamakor a secular organization founded in 2003 to promote free and open-source software in Israel.

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