Academic awards and distinctions
Ph.D. Vrije Universiteit Amsterdam. Research Fellow of the Pontifical Institute of Medieval Studies in Toronto. Professor of Philosophy at the Vrije Universiteit Amsterdam (1984-1994). Visiting Professor at the Catholic University of Leuven. Director of the Thomas-Institute at the University of Cologne (1994-2003). Since October 2003 Emeritus-Director. Vice-President of the ‘Société Internationale pour l’Etude de la Philosophie Médiévale’ (1992-2002). Cardinal Mercier Lectures at the Catholic University of Leuven; Dietrich von Hildebrand Memorial Lectures at Fordham University, New York; Directeur invité à l’Ecole Pratique des Hautes Etudes, Paris (1999); ‘Aquinas Medal Recipient’, University of Dallas (2005).

Summary of scientific research
My research is focused on three areas of medieval philosophy: 1) The thought of Thomas Aquinas, in particular his metaphysics. 2) The doctrine of the transcendental notions ‘being’, ‘one’, ‘true’ and ‘good’. The project has a historical and a systematic aspect. It investigates the history of the doctrine from its beginning in the thirteenth century (Philip the Chancellor’s Summa de bono) to the Disputationes metaphysicae of Francisco Suarez (1597), which form the bridge to the transcendental tradition in modern philosophy. The project also inquires into the systematic importance of the doctrine for philosophy in general. 3) Meister Eckhart as a ‘systematic’ thinker: A reconstruction of his Opus propositionum. As Eckhart himself indicates, ‘The Work of Propositions’ provided the foundation of the two other parts of his Opus tripartitum. However, the work has not come down to us.

Main publications
Medieval reflections on Truth, Adaequatio rei et intellectus, Inaug. Address, Free University Amsterdam, 1984; Nature and Creature, Thomas Aquinas’s Way Thought, E.J. Brill, Leiden, 1988, 413 pp. (Studien und Texte zur Geistesgeschichte des Mittelaters, Bd. 21); ‘Good as Transcendental and the Transcendence of the Good’, in: Being and Goodness, The Concept of the Good in Metaphysics and Philosophical Theology (ed. Scott MacDonald), Ithaca NY, 1991, 56-73; ‘Beauty in the Middle Ages: A Forgotten Transcendental?’, Medieval Philosophy and Theology 1 (1991), 68-97; ‘Natur, Mensch, und der Kreislauf der Dinge bei Thomas von Aquin’, in: Mensch und Natur im Mittelalter (Miscellanea Mediaevalia Bd. 21,1), Berlin-New York, 1991, 143-160; ‘The Medieval Doctrine of the Transcendentals, The Current State of Research’, Bulletin de Philosophie médiévale 33 (1991), 130-147; ‘Ontology and Henology in Medieval Philosophy (Thomas Aquinas, Master Eckhart and Berthold of Moosburg)’, in: On Proclus and his Influence in Medieval Philosophy, ed. E.P. Bos and P.A. Meyer (Philosophia Antiqua vol. 53), Leiden, 1992, 120-140; ‘Was heißt Metaphysik bei Thomas von Aquin?’ in: I. Craemer-Ruegenberg and A. Speer (eds.), Scientia und ars im Hoch-und Spätmittelalter (Miscellanea Mediaevalia, vol. 22), Berlin-New York, 1994, 217-239; ‘Gibt es eine mittelalterliche Philosophie?’ in: Philosophisches Jahrbuch 102 (1995), 161-176; ‘Albertus Magnus und die mittelalteriche Philosophie’, in: Allgemeine Zeitschrift f. Philosophie 21 (1996), 111-128; ‘Transcendental Thought in Henry of Ghent’, in: W. Vanhamel (ed.), Henry of Ghent. Proceedings of the Intern. Colloquium on the Occasion of the 700th Anniversary of his Death (1293), Leuven, 1996, 1-18; Medieval Philosophy and the Transcendentals. The Case of Thomas Aquinas (Studien und Texte zur Geistesgeschichte des Mittelalters Bd. 52), Köln-Leiden-New York, 1996; Spanish translation: La Filosofia Medieval y los Transcendentales. Un estudio sobre Tomás de Aquino, Pamplona, 2003; ‘What is First and Most Fundamental? The Beginnings of Transcendental Philosophy’, in: J.A. Aertsen and A. Speer (eds.), Was ist Philosophie im Mittelalter? Akten des X. Intern. Kongreß für mittelalterliche Philosophie der S.I.E.P.M., 25-30 August 1997, in: Erfurt (Miscellanea Mediaevalia Bd. 26), Berlin-New York, 1998, 305-321; ‘Meister Eckhart: Eine außerordentliche Metaphysik’, Recherches de Théologie et Philosophie Médiévales 66 (1999), 1-20; ‘Is There A Medieval Philosophy? I. The Case of Thomas Aquinas. II. The Case of Meister Eckhart’, International Philosophical Quarterly 39 (1999), 387-412; ‘Filosofía Cristiana: Primacia del ser versus primacia del bien’, in: Annuario Filosofico 33 (2000), 339-361; (together with M. Pickavé, eds.), Ende und Vollendung. Eschatologische Perspektiven im Mittelalter, Berlin-New York, 2003; ‘Die Umformung der Metaphysik. Das mittelalterliche Projekt der Transzendentalien’, in: J. Brachtesdorf (ed.), Prudentia und Contemplatio. Ethik und Metaphysik im Mittelalter, Wien-Zürich 2002, 89-106; ‘“Res” as Transcendental: Its Introduction and Significance’, in: G. Federici Vescovini (ed.), Le problème des transcendantaux du XIVe au XVIIe siècle, Paris 2002, 139-156; ‘Aquinas and the Human Desire for Knowledge’, in: American Philosopical Quarterly 79 (2005), 411-430; ‘Der Systematiker Eckhart’, in: A. Speer and L. Wegener (eds.), Meister Eckhart in Erfurt, Berlin-New York 2005, 189-230.

Main editor of the series
Studien u. Texte zur Geistesgeschichte des Mittelalters (Leiden/Boston) and Miscellanea Mediaevalia (Berlin/New York).

Festschriften
Die Metaphysik und das Gute. Aufsätze zu ihrem Verhältnis in Antike und Mittelalter (ed. W. Goris), Leuven 1999; Die Logik des Transzendentalen (ed. M. Pickavé), Berlin-New York 2003.