This volume constitutes the Proceedings of the "Nonlinear Dynamics in Economics and Social Sciences" Meeting held at the Certosa di Pontignano, Siena, on May 27-30, 1991. The Meeting was organized by the National Group "Modelli Nonlineari in Economia e Dinamiche Complesse" of the Italian Ministery of University and SCientific Research, M.U.RS.T. The aim of the Conference, which followed a previous analogous initiative taking place in the very same Certosa, on January 1988*, was the one of offering a come together opportunity to economists interested in a new mathematical approach to the modelling of economical processes, through the use of more advanced analytical techniques, and mathematicians acting in the field of global dynamical systems theory and applications. A basiC underlying idea drove the organizers: the necessity of fOCUSing on the use that recent methods and results, as those commonly referred to the overpopularized label of "Chaotic Dynamics," did find in the social sciences domain; and thus to check their actual relevance in the research program of modelling economic phenomena, in order to individuate and stress promising perspectives, as well as to curb excessive hopes and criticize not infrequent cases where research reduces to mechanical, ad hoc, applications of "a la mode" techniques. In a word we felt the need of looking about the state of the arts in non-linear systems theory applications to economics and social processes: hence the title of the workshop and the volume.

Contents: I. Ekeland: Some Variational Methods Arising from Mathematical Economics.- A. Mas-Colell: Four Lectures on the Differentiable Approach to General Equilibrium Theory.- J. Scheinkman: Dynamic General Equilibrium Models.- S. Zamir: Topics in Non Cooperative Game Theory.

The first ever critical edition of the monumental Commentary of St Augustine on the Psalms, a project undertaken by the Austrian Academy of Sciences (Osterreichische Akademie der Wissenschaften) and the Patristic Institute at Rome (Institutum Patristicum Augustinianum), has taken yet another step forward. The volume containing Enarrationes in Psalmos 101-109 (CSEL 95/1), edited by F. Gori (University of Urbino; Institutum Patristicum Augustinianum) with the collaboration of C. Pierantoni (Pontifical Catholic University of Chile), has now been published. The project involved the editing and collocation of numerous manuscripts. The study of their relationships revealed that the manuscript tradition had been contaminated, but not to the point of making it impossible to identify the fundamental lines of the most ancient stemmatic relationships. The construction of the text was based primarily on text criticism appropriate to its genre and to the specific forms of the Enarrationes as preached. In fact, the oratorical character of the homilies on the Psalms, their realistically oral quality, along with their spritual and parentic content, are responsible for the great fortune that the Enarrationes enjoyed in the Middle Ages. At the same time, their great circulation and their vitality during this period were also responsible for the instability of the text as witnessed in the numerous variants present in the different branches of the manuscript tradition. These variants, as important and as skillfully crafted as they are, also tax the judgments of the editors in seeking to determine which readings are authentic.

Augustines Enarrationes in Psalmos constitute a complete commentary on the Book of Psalms. They were composed as homilies he preached and as commentaries he dictated. Their rapid and widespread reception throughout the Middle Ages was due to their spiritual and moral exegesis, which monastic circles found particularly attractive. The first complete edition to be based on textual criticism and on scholarly analysis aims to replace the old Muarist text (Paris, 1681). Because of the extraordinary lenth of the complete text of the Enarrationes in Psalmos and its vast manuscript tradition the edition project has been divided among two teams working in Vienna and Rome. After the edition of the commentaries on the Gradual Psalms (Enarrationes 119-133, CSEL XCV/3, Vienna 2001), this second volume contains the exegesis of Psalms 134-140; the homilies were given in different places between the years 394 and 422.