PREFACE

A SUFFICIENT reason for a new edition of Roger Bacon’s principal work would be the extreme rarity of the edition of the Opus Majus published by Jebb in 1733, and reprinted seventeen years afterwards in Venice. But a more cogent reason is that this edition is incomplete. The work, as we learn from Bacon’s account of it in his Opus Tertium The Third Work, consisted of seven parts; and the seventh part, a discourse on Moral Philosophy, was omitted by the editor.

Why Jebb should have taken this course is not clear. In his preface he speaks of the work as consisting of six parts, ‘distributed into six parts,’ and adds, ‘he added a treatise on Moral Philosophy at the end.’ In 1858 a paper was read by Dr. Ingram before the Royal Irish Academy, and was printed in the seventh volume of the Proceedings of this institution, in which the writer showed conclusively the continuity of this seventh part of the Opus Majus with all that had gone before. The continuity is marked unmistakably in the very title of the section, Incipit septima pars hujus persuasionis de Morali Philosophia Here begins the seventh part of this treatise on Moral Philosophy, and in its opening words, ‘I have manifested in the preceding sections,’ &c. Repeated references to the foregoing parts will be found; and if