The present volume contains two short treatises by the the late fifteenth-century logician, Pere Daguí, in Latin, with English and Catalan translations, and a substantial introduction in both English and Catalan. This review is based only on the English and the Latin texts. The volume also contains, in the appendix, Bernard de Lavinheta's De formalitatibus et novem modis distinctionum, another short example of the formalist literature.
Pere Daguí may not be a household name even among scholars of later medieval philosophy, and the two short treatises contained in this volume are rather abstract and technical. Thus, the Introduction of the book is particularly helpful in situating Daguí's life as well as his work among late medieval logicians.
The first chapter, "Pere Daguí: A Biographical and Intellectual Profile," gives a detailed intellectual biography of Daguí. Daguí was born around 1435, and we learn that although we have very little information about his early intellectual formation, it is likely that he studied at some Scotist school, these being quite widespread at the time. It was with this scholastic-Scotist background that he studied the philosophy of Raymond Lull later in his life (he was around 37), which had a profound influence on his thought. Although we do not know whether Daguí ever formally belonged to the Lullian school of Barcelona, we do know that he taught in Barcelona at some point, and had some famous students there. In 1481, the Catalan Agnes de Pacs decided to found a Lullian school in Majorca, and appointed Daguí as the first professor of that school. He published his Ianua artis around the time of his appointment—a work that was later reprinted several times—±and continued teaching in Majorca, with some interruptions, until the end of his life.
We witness an interesting turn when Daguí, in the subsequent years, is accused of heterodoxy, probably because of the exceedingly heated controversy between the Thomists and the Lullists at Majorca. Daguí is called to Rome for an investigation, which finds him to be without fault. While in Rome, he probably encounters some of the Hermetic literature, as well as Ficino's neoplatonism. It is while in Rome that he also writes the first treatise on distinctions, the Tractatus formalitatum brevis, which is contained in the present volume.
When Daguí returns to Majorca, he continues facing some opposition. He starts working on his magnum opus, the Opus divinum, in 1489; it is a work that concerns metaphysics, natural philosophy, logic, and distinction theory. Perhaps as a result of some tension with a famous humanist student, Caldentey, he again leaves Majorca and teaches Lullian philosophy at the Court of Isabella and Ferdinand. He returns to Majorca, finishes his second treatise on distinctions, the Tractatus de differentia (also contained in the present volume), and dies in the same year. Although it is rather difficult to determine the extent of Daguí's influence, the Scotist-Lullist outlook remains in the Majorcan school (which became a studium generale) for a long time, influencing such figures as Alsted and even Leibniz.
The second chapter, "Tractatus formalitatum brevis and Tractatus de differentia," introduces the two texts contained in this volume. As mentioned above, both of the texts are rather difficult to read; consequently, the brief description of the main issues that we find here in the Introduction is a very helpful addition. I will return to these issues below when discussing the texts themselves.
The last part of the Introduction discusses the editorial principles. While there is no extant manuscript of either of the treatises (we are in the time when the printing press is becoming more and more widespread), the Tractatus formalitatum brevis has four incunable editions, with two different redactions. The editors make a convincing case about the chronology of these editions. They base their text on the earliest versions, while marking all the variants and inserting missing parts of the text from the later version. There are no such textual difficulties in the later Tractatus de differentia, since it survives only in a single early sixteenth-century printed edition.
As may be gathered from the biography above, Daguí treated the topic of difference in three works: in the two short treatises contained here, and in the last part of the Opus divinum. One reason why the treatises are rather difficult to read is that the topic of difference lies at the intersection of logic, epistemology, and metaphysics. As Daguí explains, following Lull, "there is no knowledge without difference" (Tractatus formalitatum brevis, §1), since "difference is the light of reason...it is that which bestows distinctness and clarity upon things and concepts'' (Introduction, 37). Thus, difference turns out to be the most difficult and most general of the principles, what Daguí calls "supertranscendent" (Tractatus de differentia, §5).
The topic of difference is of course not Daguí's invention, but was often discussed in the Scotist logical tradition, originating from various elaborations on Scotus's concept of formal distinction. Thus, we find works that influenced Daguí's treatise in Francis of Meyronnes and Peter Thomae. It is the latter author who perhaps gave the most systematic account of distinctions before Daguí's treatise, distinguishing seven kinds of distinctions (Introduction, 43-44; see Peter Thomae, Tractatus brevis de modis distinctionum.) Consequently, the main aim of Daguí's Tractatus formalitatum brevis is to explain and elaborate on these seven kinds of distinctions.
The first part of the Tractatus formalitatum brevis presents the formalist doctrine±that is, Peter Thomae's system of the seven kinds of distinctions—in a relatively clear manner. The distinctions start with the rational one, and proceed through the distinctions ex natura rei, the formal distinction, real distinction, essential distinction, and the totally subjective and totally objective distinctions. Daguí adds a further one to these traditional seven, which he calls the "numerical distinction."
The second part of the treatise discusses some of the difficulties of the theory, and elaborates on the new notion of numerical distinction. As a whole, Daguí seems to be a "critical reformer" of Peter Thomae's system (Introduction, 55); while most of the listed distinctions are the same as in Peter Thomae, Daguí argues that the last two, the totally subjective and totally objective distinctions, can be reduced to the numerical distinction. Perhaps the most interesting part of this section is the elaboration on the rational distinction. As Daguí explains, an ens rationis is not a merely mental entity in the traditional sense, like a concept, or perhaps a concept of a non-existing thing, such as a chimera (Daguí's example §19), since even though there is no corresponding reality to a concept of a chimera, it is still composed of real elements. Thus, the only entia rationis Daguí acknowledges are logical contradictions, or self-contradictory propositions, which can exist only in the mind, such as "a man is an irrational animal" (§21).
The Tractatus de differentia was written about fifteen years after the first treatise, and, as pointed out in the Introduction, is much more Lullian in character. The treatise treats the most abstract questions regarding difference. Daguí relies on Lull's notion of relations, involving three elements (the relativum, the referibile, and the referre—that which relates, that which is related, and the act of relating), and attempts to determine the nature of the difference among these concepts. Here, a new element is introduced, that of tone (sonantia), since Daguí inquires how difference works on the level of the principles themselves. As Daguí describes, principles "are said to differ because in [them] there is...difference....[But] unqualifiedly simple forms are only distinguished [due to the tone of difference], yet do not differ" (§§23-24). In other words, "items are distinguished from one another owing to the tone of difference, whereas they differ from one another owing to difference itself" (Introduction, 61). Daguí unfortunately does little to explain what exactly he means by this characterization.
Daguí's texts—especially the second one—are difficult to read, both in the original Latin and in the English translation. While the first treatise is relatively clear insofar as the descriptions of the main kinds of distinctions are concerned, some of the main concepts in the second treatise ("distinction" as contrasted with "difference," "tone," etc.) remain obscure. The topic itself is very general, and the author does little to elucidate his meaning: examples are very rarely given, and are not always illuminating.
All in all, Daguí's texts provide an interesting case-study in the later development of Lullian (and partly Scotistic) logic. The difficulty of the text is somewhat remedied by the editors' effort in helping the reader along by providing parallel texts in Lull, Peter Thomae, and occasionally Daguí's other works. The English translation is very literal, which also helps the reader to keep track of the various terms. Differentia is consistently translated as "difference"; distinctio as "distinctio"; alietas as "otherness"; sonantia as "tone"; and so on—it is in fact not too difficult to translate the English text back into Latin. Although I have no knowledge of Catalan, I assume that the Catalan translation is similarly clear.
All in all, this volume is a fine edition and translation of Daguí's short treatises. While it is difficult to asses the influence of these works, the edition will surely be welcomed by scholars of late scholastic logic, and perhaps of late scholastic Scotistic thought as well. The edition and translation may also be useful for early modernists, interested in the precursors of Leibniz's logic. While it is difficult to imagine these texts being very useful in an undergraduate medieval philosophy classroom, the English translation (or at least a short selection from it) would be a viable choice in a graduate course on late medieval scholasticism or on the history of logic.