Since this is the final volume in a series of three dealing with art theory I take the opportunity to record some of the debts I incurred in the course of studying the subject and writing its history. My main debt of gratitude goes to the libraries and to the librarians in many universities who unfailingly helped in sometimes difficult searches. I cannot list all of these, but I should not fail to mention the National and University Library in Jerusalem and its devoted staff. Shlomo Goldberg earns my special thanks for continual assistance.
In the course of writing the volumes and preparing them for publication I enjoyed the stimulating interest of Colin Jones, the former director of New York University Press. Our many lively talks over many years helped to concentrate my attention on this work, when other projects often seemed very tempting. Closer home, I should like to thank Mira Reich for continuing intelligent help in many respects. My questions, I am afraid, were not always easy ones, but she always did her utmost to find what I was looking for. I am also grateful to Luba Freedman, colleague in my department and former student, for continuous assistance in many ways.
It is now more than two decades since I began to work with New York University Press, and it is a pleasure to record my gratitude to the staff of the Press, first of all to Despina Papazoglou Gimbel, managing editor, for steady cooperation, combining prudent responsibility for the quality of the book with friendly care for its author.
My most profound gratitude I owe to my wife. Without her encouragement, strict criticism, and patience this book, as well as my other studies, could not have been written.