The revision of _The Methods of Ethics_ for this edition was begun by Professor Sidgwick and carried through by him up to p. 276, on which the last of his corrections on the copy were made. The latter portion of his revision was done under the pressure of severe illness, the increase of which prevented him from continuing it beyond the point mentioned; and by the calamity of his death the rest of the book remains without the final touches which it might have received from his hand. In accordance with his wish, I have seen pp. 277 to 509 through the press unchanged--except for a few small alterations which he had indicated, and the insertion on pp. 457-459 of the concluding passage of Book iv. chapter iii.[6] Such alterations as were made by Professor Sidgwick in this edition prior to p. 276 will be found chiefly in chapters i.-v. and ix. of Book i., and chapters iii. and vi. of Book ii. The Appendix on “The Kantian Conception of Free Will,” promised in note 1 on p. 58 of this edition, is substantially a reprint of a paper by Professor Sidgwick under that heading which appeared in _Mind_, vol. xiii. No. 51, and accurately covers the ground indicated in the note. There is one further matter of importance. Among the MS. material which Professor Sidgwick intended to be referred to, in preparing this edition for the press, there occurs, as part of the MS. notes for a lecture, a brief history of the development in his thought of the ethical view which he has set forth in the _Methods of Ethics_. This, though not in a finished condition, is in essentials complete and coherent, and since it cannot fail to have peculiar value and interest for students of the book, it has been decided to insert it here. Such an arrangement seems to a certain extent in harmony with the author’s own procedure in the Preface to the Second Edition; and in this way while future students of the _Methods_ will have access to an introductory account which both ethically and historically is of very exceptional interest, no dislocation of the text will be involved. In the account referred to Professor Sidgwick says:-- “My first adhesion to a definite Ethical system was to the Utilitarianism of Mill: I found in this relief from the apparently external and arbitrary pressure of moral rules which I had been educated to obey, and which presented themselves to me as to some extent doubtful and confused; and sometimes, even when clear, as merely dogmatic, unreasoned, incoherent. My antagonism to this was intensified by the study of Whewell’s _Elements of Morality_ which was prescribed for the study of undergraduates in Trinity. It was from that book that I derived the impression--which long remained uneffaced--that Intuitional moralists were hopelessly loose (as compared to mathematicians) in their definitions and axioms.