The introduction of a new analytical method, due fundamentally to François Viète and René Descartes and the later dissemination of their works, resulted in a profound change in the way of thinking and doing mathematics. This change, known as process of algebrization, occurred during the seventeenth and early eighteenth centuries and led to a great transformation in mathematics. Among many other consequences, this process gave rise to the treatment of the results in the classic treatises with the new analytical method, (...) which allowed new visions of such treatises and the obtaining of new results. Among those treatises is the Arithmetic of Diophantus of Alexandria which was written, using the new algebraic language, by the French mathematician Jacques Ozanam, who in addition to profusely increasing the original problems of Diophantus, solved them in a general way, thus obtaining many geometric consequences. The work is handwritten, it has never been published, it has been lost for almost 300 years, and the known references show its importance. We will show that Ozanam’s manuscript was quoted as an important work on several occasions by others mathematicians of the time, among whom G. W. Leibniz stands out. Once the manuscript has been located, our aim in this article is to show and analyze this work of Ozanam, its content, its notation and its structure and how, through the new algebraic method, he not only solved and expanded the questions proposed by Diophantus, but also introduced a connection between the algebraic solutions and what he called geometric determinations by obtaining loci from the solutions. (shrink)

In this paper which consists of two parts (Teil I and Teil II) we champion Diophantus of Alexandria and Isabella BaÅ¡makova against Norbert Schappacher. In two publications ([Schappacher 1998a] and [Schappacher 1998b]) he puts forward inter alia two propositions: Questioning Diophantus’ originality he considers affirmatively the possibility that the Arithmetica are the joint work of a team of authors like Bourbaki. And he calls BaÅ¡makova’s claim (in [BaÅ¡makova 1972]) that Diophantus uses negative numbers, a nonsense , reproaching her for her (...) thoughtlessness . Teil I: First, we disprove Schappacher’s Bourbaki thesis. Second, we investigate the semantic meaning and historical significance of Diophantus’ keywords $ λvarepsilon tildeιψιζ and ὕπαρξιζ. Next, we discuss Schappacher’s epistemology of the history of mathematics and defend BaÅ¡makova’s methods. Finally we analyse in detail three problems from Diophantus’ Arithmetica (and their solutions) given by Thomas Heath and Helmuth Gericke as proof of the their claim that Diophantus did not use negative numbers. Teil II: In this Part, we give 33 places where Diophantus uses negative quantities as intermediate results; they appear as differences a − b of positive rational numbers, the subtrahend b being bigger than the minuend a; they each represent the (negative) basis ( πλvarepsilonυρacuteα ) of a square number ( τvarepsilonτρacuteαγω ν o ζ ), which is afterwards computed by the formula (a - b) 2 = a 2 + b 2 - 2ab $ . Finally, we report how the topic Diophantus and the negative numbers has been dealt with by translators and commentators from Maximus Planudes onwards. Und er kommt zu dem Ergebnis: ≪Nur ein Traum war das Erlebnis. Weil≫, so schlieβt er messerscharf, ≪nicht sein k a n n, was nicht sein d a r f.≫ CHRISTIAN MORGENSTERN: Palmstrm. (shrink)

In this second part of “Negative Größen bei Diophant?” we start, as announced, by giving 33 places where Diophantus uses negative quantities as intermediate results; they appear as differences a − b of positive rational numbers, the subtrahend b being bigger than the minuend a; they each represent the (negative) basis $(\pi\lambda\varepsilon\upsilon\rho\acute{\alpha})$ of a square number $(\tau\varepsilon\tau\rho\acute{\alpha}\gamma\omega\nu o \zeta)$ , which is afterwards computed by the formula (a - b)2 = a 2 + b 2 - 2ab. Finally, we report (...) how the topic “Diophantus and the negative numbers” has been dealt with by translators and commentators from Maximus Planudes onwards. (shrink)

Three problems in book I of Diophantus’ Arithmetica contain the adjective plasmatikon, that appears to qualify an implicit reference to some theorems in Elements, book II. The translation and meaning of the adjective sparked a long-lasting controversy that has become a nonnegligible aspect of the debate about the possibility of interpreting Diophantus’ approach and, more generally, Greek mathematics in algebraic terms. The correct interpretation of the word, a technical term in the Greek rhetorical tradition that perfectly fits the context in (...) which it is inserted in the Arithmetica, entails that Diophantus’ text contained no (implicit) reference to Euclid’s Elements. The clause containing the adjective turns out to be a later interpolation, that cannot be used to support any algebraic interpretation of the Arithmetica. (shrink)