=3.= Ethics, in its comprehensive sense, is naturally divided into two leading parts--Theoretical Ethics, and Practical or Applied Ethics. ==Theoretical Ethics.== (1) Theoretical Ethics deals with the essential realities and principles which form the fundamental basis and source of obligation and moral law, in the constitution of man and of the world. It is a speculative study, seeking a rational account of the foundations of morality and behests of duty. It secures a theory from and of the facts. It has, however, a double range of investigation, as it seeks to determine the truth with respect to the two great essential factors in the aggregate inquiry. In the one range it examines and ascertains the facts and laws of man's moral nature. It investigates the constitution of the moral agent, in whose conscious experience, in the presence of the concrete world, the moral phenomena arise. In this part, the inquiry is psychological, and its results are scientific. In the other range it investigates the nature and ground of right, or the morally good. In this the search is not for what is discoverable within the moral agent, or the phenomena of the moral perceptions and emotions, but for that which is without him and to which his moral life is, at least apparently, required to be adjusted. Here the work is metaphysical, passing on from what is phenomenal within man, and looking for the super-phenomenal realities implied. The process and results here are philosophical. It thus appears that the one range of investigation moves subjectively, the other objectively. The first discovers what man is--at least so far as his constitution embraces those powers, perceptions, judgments and feelings in which he becomes and recognizes himself a moral being; the second seeks to know what rectitude is, or what is that to which the moral perceptions and discriminations refer and bind. When the truth on both these sides is discovered and brought together, the whole view, with the particulars logically correlated, will present the aggregate theory of duty, or the rationale of obligation. ==Practical Ethics.== (2) Practical Ethics sets forth the proper application of these fundamental principles of right and duty, as developed and justified in theoretical ethics, to the varied relations of men, personally, in the Family, in Society, and in the State. It passes on from the philosophy of moral obligations to a settlement of particular duties in the different spheres of human life and activity.