The title of the book intends to be fairly descriptive of it. It treats of ethics asa science, which if not wholly independent of mataphysical conciderations--and of no science can that be said--is sufficiently independant to permit of separate positive treatment. And under the broad license of an `introduction' it presents not only an outline of the science as we find it to-day, but some account of the past which has made it what it is. Part I contains brief chapters upon the scope and methods of the science and upon one metaphysical topic (the freedom of will) which cannot well be passed over in silence. Part II is a review of the principla Greek and English ethical theries. I Part III a positive treatment of moral problems presented in connection with the elements of the general theory of values.