tively. I have not attempted to read into the mediæval thinkers modern ideas that were foreign to them. I endeavored to interpret their ideas from their own point of view as determined by their history and environment and the literary sources, religious and philosophical, under the influence of which they came. I based my book on a study of the original sources where they were available—and this applies to all the authors treated with the exception of the two Karaites, Joseph al Basir and Jeshua ben Judah, where I had to content myself with secondary sources and a few fragments of the original texts. For the rest I tried to tell my story as simply as I knew how, and I hope the reader will accept the book in the spirit in which it is offered—as an objective and not too critical exposition of Jewish rationalistic thought in the middle ages.
My task would not be done were I not to express my obligations to the Publication Committee of the Jewish Publication Society of America to whose encouragement I owe the impulse but for which the book would not have been written, and whose material assistance enabled the publishers to bring out a book typographically so attractive.
Philadelphia,
July, 1916.
