(4) The book also contains a constructive argument, setting forth the conviction to which the author has come with regard to the faith of Abraham Lincoln.

It is entirely possible that some readers will find themselves in essential agreement with the author in the earlier parts of the book, but will dissent in whole or in part from his own inferences. Whether the reader agrees or disagrees with the author in his conclusions, he will find in this book some material not elsewhere available for the formation of an independent judgment. Nevertheless the author counts himself justified not only in adducing the evidence but in stating frankly the conclusion which to his mind this evidence supports.

This book treats of the religion of Abraham Lincoln; but it does not consider his religion as wholly expressed in his theological opinions. Important as it is that a man should think correctly on all subjects, and especially on a subject of such transcendent value, religion is more than a matter of opinion. We cannot adequately consider religion apart from life. Abraham Lincoln's life was an evolution, and so was his religion. In a way which this volume will seek to set forth, Lincoln was himself a believer in evolution, and his life and religion were in accord with this process as he held it.

This book is, therefore, more than an essay on the religion of Lincoln, unless religion be understood as inclusive of all that is normal in life. It deals, therefore, with the life, as well as with the opinions, of Lincoln; and it considers both life and opinion as in process of development in each of the successive stages of his career.

In this respect the present book may claim some distinctive place in the literature of this subject. Other books have drawn sharp contrasts between the supposed religious opinions of Lincoln's youth and those which he is believed to have cherished later. This book undertakes what may be termed a study of the evolution of the spiritual life of Abraham Lincoln. The author is not aware that this has been done before in quite this way.

The author acknowledges his obligations to many friends for their assistance in the preparation of this volume. Mr. Jesse W. Weik, of Greencastle, Indiana, associate of Mr. Herndon in the preparation of his Life of Lincoln, and owner of the Herndon manuscripts, has been generous to me. Mrs. Clark E. Carr, of Galesburg, Illinois, widow of my honored friend, and the friend of Lincoln, Colonel Carr, author of "Lincoln at Gettysburg," has placed at my disposal all her husband's books and papers. Mr. Judd Stewart, of New York City, owner of one of the largest collections of Lincolniana, has assisted me. President John W. Cook of the Northern Illinois State Normal School has suggested important lines of research. Mr. John E. Burton, of Lake Geneva, Wisconsin, whose collection of Lincoln books was once the largest in America, has sold me some of his chief treasures, and imparted to me much of the fruit of his experience. Mr. O. H. Oldroyd, of Washington, owner of the famous Lincoln Collection, and custodian of the house where Lincoln died, has, on two visits, placed all that he has within my reach. To these, and to a considerable number of men and women who knew Lincoln while he was yet living, and to many others whom I cannot name, my thanks are due.

I regret that one great collection, consisting, however, more largely of relics than of manuscripts, is so largely packed away that it has not been of much use to me. Mr. Charles F. Gunther of Chicago has, however, produced for me such Lincoln material as seemed to him to bear upon my quest, and I acknowledge his courtesy.

Mr. Oliver P. Barrett of Chicago has given me great joy in the examination of his fine collection of Lincoln manuscripts.

I have spent a few pleasant and profitable hours in the collection of Honorable Daniel Fish, the noted Lincoln bibliographer, of Minneapolis, and thank him for his friendly interest in this undertaking.

Among libraries, my largest debt is to those of the Chicago Historical Society, the Illinois State Historical Society at Springfield, and the Library of Congress in Washington. In each of these I have had not only unrestricted access to the whole Lincoln material possessed by them, but the most generous and courteous assistance. I have examined every rare Lincoln book, and many manuscripts, in these three collections. I have had occasion also to use the Chicago Public Library, the Newberry Library, and the Library of the University of Chicago, as well as those of Chicago Theological Seminary and McCormick Theological Seminary. In certain important local matters, I have been assisted by the libraries of Knox College, Galesburg, Illinois, Illinois College, Jacksonville, Illinois, the Public Library of Peoria, Illinois, and the library of Transylvania University at Lexington, Kentucky. I also visited the Public Library of Louisville, with its historical collections, but most that I found there I had already consulted elsewhere. The New York Public Library and the Library of Columbia University supplemented my research at a few important points. The Oak Park Public Library has been constantly at my service. The Library of Berea College, Kentucky, has given me very valuable assistance in finding for me a large amount of periodical literature bearing on my study. The five great Boston libraries would have yielded me much had I come to them earlier. While the book was undergoing revision, I visited the Athenaeum, the Massachusetts State, the Boston Public, the Massachusetts Historical, and the Harvard University libraries. It was gratifying to discover that even in the last named of these, enriched as it is with the collections of Charles Sumner, Thomas Wentworth Higginson, and the Lincoln collection of my friend Alonzo Rothschild, author of "Lincoln, Master of Men," there was practically nothing relating to this subject which I had not already seen and examined. In the Massachusetts Historical Library, however, I discovered some manuscripts, and that quite unexpectedly, which afford me much aid in a collateral study.