A difficulty of a more radical kind meets us, at the very outset of our inquiry, in the distinctively ethical notion expressed by the word "ought." Various attempts have been made to surmount or circumvent this difficulty; and some of these will come under consideration in the sequel. The very notion of conscious activity contains the idea of bringing about something which does not yet exist. It involves a purpose or end. The notion "ought," it is true, means more than this: it implies an obligation to pursue a definite end or conform to definite rules, regarded generally as coming from an authoritative source. In this clear and full sense, "oughtness" or duty is a comparatively recent notion, foreign to the classical period of Greek ethics. The force and definiteness belonging to the modern conception of it are due to the juridical aspect which the Stoic philosophy, Roman law, and Christian theology combined to impress upon morality. But even the notion of purpose or end implies a "preference" of the end sought: the state to be realised is looked upon as "better" or "more to be desired" than the existing state. We may ask for the reason of this superior desirableness; but the answer must soon fall back upon the assertion of something held to be desirable in itself. The question which we are always asking, and cannot help asking, "Why is such and such an end to be pursued by me?" or "Why ought I to follow such and such a course of conduct?" must soon lead to the assertion of an ultimate end. [Sidenote: the transition to which requires investigation;] This end, therefore, must not be sought for some ulterior end, nor desired as a means to satisfy any other desire. But it is still necessary to inquire into the way in which the end, held to be ultimate in a practical regard, stands related to the constitution of man and his environment. And the question to which I would draw attention, as the fundamental problem of ethics, is, What is that which men have variously called happiness, the highest good, the ethical end? or, more precisely, How can a transition be made from the notions of theoretical philosophy to the determination of that ethical end? No assumption is made, at starting, as to the nature of this end, or the manner of arriving at it. It may be a transient state of feeling, or a permanent type of character; or it may by its very nature defy exact definition,--the idea itself being perfected as its realisation is progressively approached. In any case it requires to be brought into connection with the ultimate conceptions of thought and existence.