This book has been prepared, particularly, for the use of the Freshman Class in Harvard College. The author has, at the same time, desired to meet the need, felt in our high schools, of a manual of Moral Science fitted for the more advanced classes.In the preparation of this treatise, the author has been at no pains to avoid saying what others had said before. Yet the book is original, so far as such a book can be or ought to be original. The author has directly copied nothing except Dugald Stewart's classification of the Desires. But as his reading for several years has been principally in the department of ethics, it is highly probable that much of what he supposes to be his own thought may have been derived from other minds. Of course, there is no small part of the contents of a work of this kind, which is the common property of writers, and must in some form reappear in every elementary manual.