Jeudi 16 mars 2023 – Séminaire CHSPAM – Journée “La perfection des espèces et le fondement métaphysique de la science médiévale”

“Sciences et philosophies de l’Antiquité à l’Age classique” du Centre d’Histoire des Sciences et des Philosophies Arabes et Médiévales (CHSPAM)

La perfection des espèces et le fondement métaphysique de la science médiévale

organisée par Sabine Rommevaux-Tani (CNRS, SPHere) et Daniel A. Di Liscia (Ludwig-Maximilians Universität München)

Jeudi 16 mars 2023 – Séance en distanciel – lien d’accès accessible dans l’encadré

 

PROGRAMME

9:30 Introduction

9:45 – 10:45 Philippe DEBROISE (SPHere) Nicole Oresme et la perfection des espèces : un simple problème métrique ?

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11:15 – 12:15 Daniel A. DI LISCIA (Ludwig-Maximilians Universität München) Jacob of Naples’ Treatise on the Perfection of Species

14:00 – 15:00 Andrea NANNINI Divine ideas, multiplicity and replicatio unitatis divinae : John of Ripa’s de perfectione specierum

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15:30 – 16:30 Sylvain ROUDAUT (Stockholm University) An original philosophical synthesis : Paul of Venice’s theory of the perfection of species

16:30 Conclusion

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RÉSUMÉS

9:45 – 10:45 Philippe DEBROISE (SPHere) Nicole Oresme et la perfection des espèces : un simple problème métrique ? Dans ses questions sur la Physique d’Aristote, Nicole Oresme s’intéresse à la question générale de la perfection des espèces pour des raisons essentiellement métriques : il s’agit pour lui de définir une échelle mathématique singulière, qui satisfasse les propriétés métaphysiquement requises par l’ordre des êtres en perfection. Parce que cette mesure des êtres est non-proportionnelle, elle conduit Oresme à approfondir l’idée mathématique de mesure en l’augmentant d’un concept original de la comparatio, qui mobilise en particulier une analyse géométrique très fine de l’angle de contingence et des angles mixtilignes. Néanmoins, cette question métaphysique n’est-elle pour Oresme qu’une occasion quelque peu artificielle de faire montre de subtilités mathématiques ? Ou bien, au contraire, cette mathématisation a-t-elle elle-même un sens métaphysique ? Je présenterai la mathématisation du problème par Nicole Oresme telle qu’on peut la comprendre à partir à la fois de son commentaire sur la Physique et de ses Questions sur la géométrie d’Euclide. J’insisterai sur l’importance mathématique de ces travaux : la métaphysique oblige Oresme à approfondir l’outillage conceptuel mathématique insuffisant en lui-même. Mais j’étendrai mon propos, à l’aide d’autres textes d’Oresme ou attribués à Oresme, sur la signification métaphysique de cette mathématisation.

11:15 – 12:15 Daniel A. DI LISCIA (Ludwig-Maximilians Universität München) Jacob of Naples’ Treatise on the Perfection of Species  Introduced more than fifty years ago by Anneliese Maier, the name of “Jacobus de Napoli” seems to have attracted only minor attention until I – following Maier’s pioneer research and some remarks by John Murdoch – pointed out that his Tractatus de perfectione specierum could have been a pivotal text of a widespread medieval tradition tending to ensure a more determining role to geometry within theology and metaphysics. As a matter of fact, this treatise continued – and to a certain extent also transformed – the until then rather physically orientated calculatores tradition. In my talk, I would like first to discuss the problems of the identification of this author. Second, I will give a short account of the (manuscript) sources. Third, I will discuss the content of the treatise in its main lines. In addition, I will offer some details regarding the only one known commentary on this text. Overall, my talk will be a compact presentation of the edition of this text I am preparing for publishing in this year. For this reason, I will also include some specific philological questions related to the text itself and the critical apparatus.

14:00 – 15:00 Andrea NANNINI Divine ideas, multiplicity and replicatio unitatis divinae : John of Ripa’s de perfectione specierum  The thought of John of Ripa, metaphysically developed in the central distinctio secunda of his Lectura, puts a lot of emphasis on the concept of divine immensity. The super simplicity of God prevents His perfection to have a latitudinarian expression, measurable in a series of degrees of intensity ; on the contrary, any possible creature has necessarily a latitudinarian and gradual expression for each of its perfections (denominationes perfectionis), which prevents it to reach God’s supersimplicity. Thus, God’s immensity can be envisioned as the metaphysical origin of any possible perfection, in an analogical form that requires a mechanism of communication ad extra which donates to the created domain any possible perfection originally contained in the divine essence without confounding creatures with God. Creatures will share univocally all the common perfections analogically provided by God, while the degrees of intensity of these expressions will differentiate one creature from another. The metaphysical device chosen by Ripa, defined as replicatio unitatis divinae, provides multiple and overlapped latitudes to the created domain – one for each perfection (denominatio perfectionis) – creating an ordered framework where any species and its individuals find their precise collocation. Hence, the perfection of species (perfectio specierum) has its roots in God’s essence, since the peculiar notion of “divine idea” provided by John of Ripa collects and converges any perfection’s latitudinarian communication ad extra in a single divine idea of immense perfection, as Ripa states in the unedited distinction thirty-five of his Lectura.

15:30 – 16:30 Sylvain ROUDAUT (Stockholm University) An original philosophical synthesis : Paul of Venice’s theory of the perfection of species  Paul of Venice (ca. 1369–1429) stands out as one of the greatest metaphysicians of the late Middle Ages and one of the most important philosophers of early 15th-century Italy. Unlike other aspects of his metaphysics like his views on universals, his theory of the perfection of species has received little attention from scholars. This talk will be devoted to presenting the main ideas of Paul’s conception of the perfection of species. The first part of the talk will present a detailed analysis of the many sources from which Paul builds his theory : 1) the Parisian tradition broadly understood, i.e. including both Arts Masters and theologians of the mid-14th century ; 2) the Oxford Calculators to whom Paul borrows quantifying techniques that he applies to metaphysical objects ; 3) the geometrization trend found in earlier treatments of the problem ; 4) the realist traditions of John of Ripa and John Wyclif. The second part of the talk will show how Paul constructed from these many sources a consistent and unified theory of species that represents in many respects one of the most powerful theories of the perfection of species designed in the Middle Ages.

http://www.sphere.univ-paris-diderot.fr/IMG/pdf/chspam_16-03-2023.pdf