of sight the difficulties of the subject; either unconsciously, from a latent conviction that the questions which the writer cannot answer satisfactorily must be questions which ought not to be asked; or consciously, that he may not shake the sway of morality over the minds of his readers. This last well-meant precaution frequently defeats itself: the difficulties thus concealed in exposition are liable to reappear in controversy: and then they appear not carefully limited, but magnified for polemical purposes. Thus we get on the one hand vague and hazy reconciliation, on the other loose and random exaggeration of discrepancies; and neither process is effective to dispel the original vagueness and ambiguity which lurks in the fundamental notions of our common practical reasonings. To eliminate or reduce this indefiniteness and confusion is the sole immediate end that I have proposed to myself in the present work. In order better to execute this task, I have refrained from expressly attempting any such complete and final solution of the chief ethical difficulties and controversies as would convert this exposition of various methods into the development of a harmonious system. At the same time I hope to afford aid towards the construction of such a system; because it seems easier to judge of the mutual relations and conflicting claims of different modes of thought, after an impartial and rigorous investigation of the conclusions to which they logically lead. It is not uncommon to find in reflecting on practical principles, that--however unhesitatingly they seem to command our assent at first sight, and however familiar and apparently clear the notions of which they are composed--nevertheless when we have carefully examined the consequences of adopting them they wear a changed and somewhat dubious aspect. The truth seems to be that most of the practical principles that have been seriously put forward are more or less satisfactory to the common sense of mankind, so long as they have the field to themselves. They all find a response in our nature: their fundamental assumptions are all such as we are disposed to accept, and such as we find to govern to a certain extent our habitual conduct. When I am asked, “Do you not consider it ultimately reasonable to seek pleasure and avoid pain for yourself?” “Have you not a moral sense?” “Do you not intuitively pronounce some actions to be right and others wrong?” “Do you not acknowledge the general happiness to be a paramount end?” I answer ‘yes’ to all these questions. My difficulty begins when I have to choose between the different principles or inferences drawn from them. We admit the necessity, when they conflict, of making this choice, and that it is irrational to let sometimes one principle prevail and sometimes another; but the necessity is a painful one. We cannot but hope that all methods may ultimately coincide: and at any rate, before making our election we may reasonably wish to have