The Secret Faith of Maestre Honoratus. Maud Kozodoy

apply the same term to the Jew Hasdai Crescas, whose investigations of motion and critique of Aristotelian physics were not aimed in the least at learning about the natural world but rather at countering the radical philosophical tendencies he believed were undermining Jewish faith in his time. In addition, the more technological and number-reckoning sides of science, such as those involved in constructing astrolabes and quadrants and making and using astronomical tables and ephemerides, or, for that matter, professional engagement in medicine or astrological prognostication, are also excluded by the designations “philosopher-scientist” and “natural philosopher.”

      Here I will instead employ the words science and scientific activity with the understanding that, depending on the context, they may indicate vastly differing levels and registers of work and study. Where possible, in order to avoid the strong associations of the word “scientist” with modern ideas of science, I will use more specific terms like astronomer, instrument maker, astrologer, physician, and so on.

      The Duran-related texts examined below are by individuals whom we can place in a particular world and culture. They include letters copied and preserved outside their original context, scientific texts with marginal notations, a collection of writings by Duran put together by one of his students, and a rare example of class notes jotted down by another student. The texts are closely tied to their time and place, a part of material culture containing the physical trace of human hands as well as of a human mind.

      MS PARIS BNF HÉB 1023

      Our first source is a manuscript that contains approximately thirty folios of notes taken down by a student of Duran.¹² Preceded by two astronomical works—a commentary on the ninth-century Elements of Astronomy by al-Farghānī (Kitāb fi-l-ḥarakāt al-samāwīya wa-jawāmiʿ ʿilm al-nujūm, a nonmathematical summary of Ptolemaic astronomy translated into Hebrew by Jacob Anatoli) and an abridgment of that same work—and followed by a selection in Hebrew translation of treatises by well-known Arabic philosophers, the notes record brief mathematical techniques: how to multiply spherical fractions, how to find a square root, and so forth, often illustrated with diagrams or examples. There are also numerous comments on how to use astronomical tables or observational instruments. Marginal notes in the student’s hand are also found on the first item in this manuscript, the commentary on al-Farghānī.

      The student who recorded these notes seems to have been working from other texts, sometimes extracting passages from them. When extracts are presented, a heading notes the source and sometimes indicates whether the manuscript is in the author’s or another’s hand. For example, an anonymous commentary on the twelfth-century work on planetary astronomy by the Barcelona astronomer and astrologer Abraham bar Ḥiyya (Ḥeshbon mahalakhot ha-kokhavim [“Calculation of the Paths of the Planets”])¹³ is said to come from a book of Duran’s “in the handwriting of someone else,”¹⁴ suggesting that the student is extracting the glosses from a manuscript Duran himself had copied (or perhaps just purchased), and that the marginal comments are in someone else’s handwriting. Again, comments on what look to be Gersonides’ astronomical tables are said to be from a book of Bonet Bonjorn, written with “his [own] fingers.”¹⁵ Some of these constitute very brief snippets from works like Ptolemy’s Almagest, while others are longer extracts from, for example, a letter by Duran himself on the true and median conjunctions.

      It is not possible to say whether these jottings were the work of days or weeks or years. The hand is the same throughout, but with sufficient deviations in ink, pen, and speed to make it clear that the notes were not copied formally and sequentially from a preexisting text but added as the material came to hand. The diagrams tend for the most part to be fitted into the text, with the words flowing around them. What we seem to be seeing is the progress of a student’s learning. While there are no explicit references to other students, sometimes the writer varies the first person singular—“a question that I asked”—with the first and third person plural—“we wanted to find” or “the doubt that they raised with him”—suggesting that he was not working alone.

      Evidence from the University of Paris shows that medical students in that highly institutionalized setting took notes in a wide variety of formats, one of which was loose sheets, sometimes two to three folios kept as flyleaves in manuscripts; that is likely what we are seeing here as well.¹⁶ They also took notes in the margins of their texts, again seen here. What we do not find in this manuscript, however, are the sorts of study aids that Paris medical students added to their textbooks: titles given in running heads, marks for chapters and subdivisions, quick reference signs, or schematic diagrams of a work’s contents for help in memorization.

      Traces of face-to-face encounters do appear in these pages, as when the student reports that “I heard [it] from the Efod” or “from the mouth of the Efod” or “as the Efod taught me about the doubt which I asked him” or “this too I heard from him.”¹⁷ Sometimes a source is only cryptically indicated, as in the case of an otherwise unidentified maestre Bonjudas¹⁸ who has provided mathematical techniques to find the square of a number that is a multiple of one hundred, the square of a number that is between one and one hundred, and a rule regarding the ratio of a number to its square.¹⁹

      The same Bonjudas is also the source of two separate groups of brief astronomical answers. One covers the following subjects: why we see the moon as full one or two days before it is actually full; why we don’t see it at all at the time of the conjunction; a question about the term for the ecliptic; and why up to four hours can elapse between the true and the median conjunction.²⁰ The student has appended to these passages an extract from the letter Duran wrote to Shealtiel Gracian on just this topic of the difference between the true and median conjunctions. Maestre Bonjudas himself is cited with no comment beyond his name, suggesting perhaps that he was so well known to our student that no more need be said; perhaps he, too, was part of the study group. Later comments are headed by even less easily identifiable acronyms.²¹

      In this particular class, Duran was instructing students on such matters as the multiplication of spherical fractions; checking work by “casting out nines”; using astronomical tables and their canons for calculating the position of the sun and moon; taking account of error in observations using an astrolabe, a quadrant, or a saphea; gelosia (lattice) multiplication; and other highly practical astronomical techniques.²² Given what we know about the practical needs of astrologer-astronomers, it is thus likely that the students were acquiring the skills necessary to practice astrology either as an independent activity or, presumably, as a supplement to medicine. The material is highly pragmatic in purpose, and indeed reflects a relatively “low” register of scientific activity. All the more fascinating, then, since this level of activity and learning does not usually leave traces in the written record.

      Although the language of the notes is Hebrew, there is no other overt sign of the Jewishness of either teacher or pupils. Only once does a “religious” reference appear, when the note taker mentions giving thanks to “the Creator of the universe,” and even there he is quoting from his source.²³ Names of Jewish astronomers and mathematicians are given in their Catalan form next to citations of Ptolemy and al-Battani, and much of the extracted scientific material appears without reference to the nature or background of its source. This is Jewish science, then, only in the banal sense that it is being done by Jews. And yet the fact that they write their mathematics in Hebrew rather than in the vernacular of their everyday lives should not be dismissed. In itself it constitutes a sign, unspoken and perhaps even to some extent unconscious, of Jewish identity.

      MS PARMA BIBLIOTECA PALATINA 2290

      A second source is a collection of Profayt Duran’s writings put together by another student, in this case one whose name we know: Meir Crescas.²⁴ Crescas’s interests seem to have pointed him to material quite different from that just discussed: specifically, the numerological legacy of Abraham ibn Ezra. The compilation includes an eight-line poem by ibn Ezra built around the first ten numbers; according to Crescas, the poem was customarily recited in Barcelona at the afternoon service of Yom Kippur. It is accompanied by Duran’s explanation of the poem’s meaning, an explanation said here to have been written at the request of the two sons of Benveniste (ben