1. Ethics is the science of rectitude and duty. It treats of the right and its obligations. Its subject is morality. Its sphere is the sphere of virtuous conduct. It covers a double range of inquiry, as the subject-matter lies within or without the human constitution. On the one side it investigates and sets forth the facts and laws of man's moral constitution; on the other, the nature and grounds of the distinction of right and wrong. In the light of the whole investigation into these fundamental verities, it determines the principles and rules of duty in the various relations of life. It thus discovers and elucidates the underlying pre-suppositions and principles upon which the phenomena of moral discernment and obligation rest, and on which man rises into the possibility and reality of character, as his supreme distinction among the orders of existence on earth. The inquiry throughout is conducted according to the scientific method of careful observation and analysis of the unquestionable facts concerned, and an orderly presentation of their necessary logical implications and conclusions. Hence the product of the investigation, as the systematized view of the facts, with their underlying principles, may justly be called, as it usually is called, moral science.

The term Ethics, which we thus use to designate this branch of study, with its systematized truth, is not employed with etymological strictness. For it comes from the Greek ???? [Greek: Êthos], moral character, which, according to Aristotle is derived from ???? [Greek: ethos] custom, under the notion that moral virtue is a product of repeated acts of voluntary preference.1 Taken strictly this would build rectitude or the ethically right on the mere habits or usages of a people. But this conception of the basis of virtue must not be included and carried into the scientific use of the word, or be at all allowed to prejudice the final decision of this great question of the foundation of right, in the end, in the light of all the facts in the case.2

The Latin equivalent for ???? [Greek: Êthos] was mos, with similar suggestion as to the nature of rectitude, and human duty was treated under the head of De Moribus. Cicero says: "Quia pertinet ad mores, quod ???? [Greek: Êthos] illi vocant, nos eam partem philosophiÆ De Moribus appellare solemus; sed decet augentem linguam Latinam nominare Moralem."3 This suggestion of Cicero has given the common English designation Morals or Moral Philosophy. Recent usage, however, speaks of the study rather as moral science, in harmony with the prevailing preference for the term science in all investigations conducted under the inductive method. It is, nevertheless, as will appear, largely a metaphysical and philosophical investigation, and, if classed as science, must be counted as pre-eminently a philosophical science.

2. The beginning of the movement to give a systematic view of ethical truth may be traced to Socrates. The pre-Socratic philosophy failed to produce anything that can be called a system in this connection. The difficulty in the way was not only the want of a scientific spirit at that period, but especially the inadequate and false light in which human beings were viewed. Outside of the Hebrew people there was little or no recognition of the freedom of man, as man. Such freedom was denied both in thought and in life. Everywhere, in India, China, and Egypt, as well as in Greece and Rome, the immense mass of the population were in a condition of abject slavery, regarded as chattels, not amenable to the responsibilities of moral life. Only the free citizens were viewed as capable of virtue. Slavery was a part of the very conception of the State. The essential characteristics and rights of humanity were not thought of as belonging to all men. But moral life, as will appear, can exist only in the sphere of liberty. Even the most advanced philosophers of the ancient world extended the conception of moral manhood only to the free citizen, the status of the rest not bringing them within the possibility of even civic virtue. And even the so-called free citizen existed almost absolutely for the State. His sacred selfhood disappeared under ownership by the Government, by which he was held and used as a machine for military service. Even long after Socrates opened the way, within this limited range, toward some connected view of ethical life, these disabling causes continued to distort and impede all efforts to systematize the principles which underlie and determine it. Plato, Aristotle, and the philosophers generally, continued to know nothing of a morality for all human beings.4

It is to be remembered, too, that this tardy appearance of effort in scientific ethics is part of the wider fact, that in that period of human history even the most advanced tribes and nations had not risen to science at all. All knowledge was in the non-scientific form, or only fragmentarily and inchoately adjusted. The moral consciousness and personal virtues, however, of course existed, as part of the normal constitution and practical activities of human life. The various peoples had collections of moral precepts and rules for right living, often bright with gems of ethical truth and beauty, usually in close connection with religious beliefs and convictions; but these were not based and unified on any underlying principles bringing them logically into compact and consistent system. Just as the facts and practices of religion existed, in even rich luxuriance, anterior to the appearance of speculative theologies, and the phenomena of nature for long centuries preceded the formation of the natural sciences, so the moral constitution of the race and practical morality existed long in advance of the explanations and systemization that create the science of ethics.

The history of the science does not come within the purpose of this work. The greatness of the speculative and practical questions involved in the subject, clearly and impressively apparent when once brought forward, could not fail to awaken and hold the most earnest interest of the human mind. They concerned the powers and possibilities of man in the crowning endowments of his nature, and in the highest ascent of their evident intention and adaptation. They touched the great problems of personal and social welfare in the most vital relations and decisive interests. So the old sages became moralists and their great themes were the themes of virtue and duty. Not very deeply, however, did they, for centuries, succeed in penetrating the rational principles of the moral life and the authority of the moral judgments. Yet clear gems of thought and deep suggestion mark the pathway of their thinking. In passing on, and over from pagan into Christian development, the treatment was mostly in connection with religious truths, and as involved in theological doctrine. In the light of the Christian Scriptures the whole subject came under a new illumination. The various duties, however, in the different relations of life, were permitted to rest, without much theorizing, on the warrant of supernatural revelation and divine precept. Down through the early Christian period, and the centuries of mediÆval scholasticism, and on through the Renaissance and the Reformation and the subsequent dogmatic period of Protestant theology, ethics continued to be treated simply as a division of theology, based almost wholly on the Sacred Scriptures, with but little inclusion of any effort to determine its natural basis and significance. But with the age of modern philosophy and science a new interest and direction came to ethical inquiry. Explanation began to be sought for the unique authority of the ethical judgments, and concerning the place of the moral power in the essential constitution of the human soul. Special emphasis was given to the fact that, even apart from the precepts of revelation, man is bound to rectitude by an imperative within him, which is not of his choice, but claims the right to dominate his choices. And since the seventeenth century the ethical constitution of humanity, together with the nature and grounds of right, has been made, apart from theology, the distinct and separate theme of scientific and philosophical investigation and discussion. It has been among the leading subjects of rational inquiry and constructive effort. Especially in Great Britain and in our own country has the inquiry been conducted on this basis, and directed to the exhibition of the natural foundation and character of the ethical distinctions and judgments, and to a systemization of the ethical realities and laws thus determinable. The work thus done has created an immense literature, and established a body of securely authenticated scientific results.

3. Ethics, in its comprehensive sense, is naturally divided into two leading parts—Theoretical Ethics, and Practical or Applied 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.

(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.

The connection between theoretical and practical ethics is very close and vital. Theory and practice always affect each other. They cannot be held wholly apart. They act and react on each other, in ceaseless influences. It is so in every department of thought and life. Theoretical error in physical science, in art, in trade, in political economy, can hardly fail to appear in faulty or misdirected practice. Every failure to grasp first principles correctly and firmly is sure to mean failure also to grasp and maintain the true order and beauty of right living. False views as to the reality and grounds of moral obligation weaken, vitiate and corrupt life. They become, often, the fountain of far-flowing streams of evil and blight. At best they lack power for the true and right life. A correct theory of ethical truth is, therefore, demanded by all the high interests in the moral life of man and the order of the world.

It is apparent, however, that it is only the theoretical part that constitutes the science of ethics. It alone settles the systematic view of it, revealing its underlying pre-suppositions and principles, exhibiting its reasons and determining its laws. Practical ethics, as simply pointing out how these bear upon men's temper and conduct in actual life, is apart from the scientific investigation. Though this has usually constituted a large portion of formal treatises on the subject, we, for the reason thus given, omit it from this discussion.

4. A few of the relations of ethical science are properly called to mind here. Its place will thus be more clearly seen. It sustains very close relations to three other great branches of study.

(1) To psychology. It is organically related to this. In that part of its work which determines the reality and nature of moral obligation from the constitution and action of the human mind, moral science joins with psychology in the investigation of man's mental capacities and powers. Ever since the days of Aristotle ethics has been seen to have real psychological basis and pre-suppositions.5 Yet, as a result of the later general subsuming of ethics under religious and theological precepts, this basis received but little distinct investigation till the time of Shaftesbury who, though failing to give adequate or correct account of it, brought it prominently forward. Mental science is essentially conditional for moral science. The behests of duty are provided for and sanctioned in human nature. The moral discriminations and convictions emerge as psychical phenomena. "To understand what man ought to do, it is necessary to know what he is." In the very structure and adjustment of his powers, it becomes apparent that he has been made for duty and organized under obligations.

But while psychology and ethics both study the powers and functions of the soul, they do so with different aims. The one has no aim beyond a knowledge of the phenomena and laws of the mind as mind. The other studies it with a view to the light which this knowledge sheds on the problems of virtue and duty. There are, indeed, some questions in ethics that transcend the province of psychology, and belong to the further realm of metaphysics—as, for instance, the validity and ground of the distinction between right and wrong—yet, so far as it is the science of conscience or of man's moral nature, it is thoroughly psychological. And well would it have been for moral science if, instead of speculatively and arbitrarily theorizing on the subject, it had more critically, fully, and exactly searched out the real facts in actual psychology and moved forward always toward the conclusions necessitated by these fundamental and abiding realities.

(2) To Natural Theology. As Natural Theology seeks to determine the existence, character and will of God as Creator and Moral Governor of the world, and the consequent relations and responsibilities of men, it covers, to some extent, the same ground as a system of ethics constructed simply upon the basis of reason and the data found in man's nature and place. Both, if properly drawn out, bring to view the reality of "a power that makes for righteousness"6 in the natural constitution of the world, and exhibit the laws of obligation that bind men under the action of conscience. Both treat of the fact and authentications of human duty. A science of ethics, as well as a theology, may be constructed, apart from supernatural revelation, from the data of reason and nature alone. The possibility of this is implied in Rom. 2:14, 15. This would be a system of natural ethics. There is still, however, a large difference—though theology and ethics be kept apart from the teachings of special revelation. For Natural Theology keeps more prominently and controllingly in view the being and character of God, and aims more distinctly to produce the religious sentiments, while authenticating the reality and action of the moral law. Ethics, on the other hand, puts the facts of human nature and life into the front and includes the religious element only as a consequential, though necessary, inclusion.

(3) To Christian Theology, or revealed religion. As this is the fullest disclosure of the duty of man, in all his relations, to God, to his fellow-men, and to his own end, it is not surprising that for so many centuries, the treatment of morals was made simply a part of general theology, and merely distinguished as Moral Theology. In the modern separation of ethics from theology and treatment of it as a science, it is not meant to deny the close affinity between the two investigations or the rich illumination that duty receives from supernatural revelation, but only to trace out more distinctly and fully, in independent and scientific form, the deep and immovable foundations of the principles of duty in the very constitution of man and the world. This exhibition of the natural basis of ethical law and obligation becomes an independent and generic enforcement of the principles of righteousness. It gives a philosophic vindication of one of the first assumptions of Christianity—the supremacy of the law of rectitude for human life. And Christianity is vindicated and exalted when it comes recognizing and confirming all the principles and duties discoverable in our moral nature, and adding a supernatural disclosure of the way in which righteousness may be established in our lives, and men may attain their right character and destiny.

Christianity, while much more than this, appears as a divine re-publication of the ethical truth which from the first has been incorporated in the organization of humanity. In it the light of conscience is supplemented and made clear. The ethics of human reason and those of revelation thus cover, to a great extent, the same ground. When correctly read they are never in conflict, but in harmony. Both show man to be under moral law—and under broken law, that is, under sin. But the light of the Scriptures is broader and fuller. For in addition to their confirmation of a natural ethic for man, they disclose a scheme of redemption, with otherwise undiscoverable moral relations and obligations, introducing new and vital elements into the science of ethics. The inclusion of these elements and truths turns pagan or natural ethics into Christian.

Whatever interpretation may be given by different Christians to the redemption thus disclosed, the ethical teaching of the Sacred Scriptures, by universal consent, surpasses, in clearness, elevation and completeness, every other ethical view or system in the world. The loftiest philosophical thought has reached no higher summit—and has climbed to its best only in the light which Christianity has supplied. No system of morals is now worthy of the name that fails to avail itself of its ethical teaching. Only when this is properly included, illuminating natural ethics with its supernatural light, can we have the whole view of human duty. He who refuses the Christian grade and completeness of moral view goes back from the full daylight into the obscure dawn before the morning. Nevertheless the natural basis of ethical laws needs to be clearly apprehended and distinctly borne in mind. In these days when the foundations of all truths are put to scrutinizing tests, it is of fundamental importance that, through the verifying processes of careful science, we shall recognize the ethical verities and responsibilities, affirmed by revelation, as primarily and immutably a part of the very nature of man and the constitution of the world.