Some writers, on this account, are disposed to regard Ethics as an art rather than a science, and indeed, like every normative science, it may be regarded as lying midway between them. A science may be said to teach us to know {14} and an art to do: but as has been well remarked, 'a normative science teaches to know how to do.'[3] Ethics may indeed be regarded both as a science and an art. In so far as it examines and explains certain phenomena of character it is a science: but in so far as it attempts to regulate human conduct by instruction and advice it is an art.[4] Yet when all is said, in so far as Ethics has to do with the volitional side of man,--with decisions and acts of will,--there must be something indeterminate and problematic in it which precludes it from being designated an exact science. A certain variableness belongs to character, and conduct cannot be pronounced good or bad without reference to the acting subject. Actions cannot be wholly explained by law, and a large portion of human life (and that the highest and noblest) eludes analysis. A human being is not simply a part of the world. He is able to break in upon the sequence of events and set in motion new forces whose effects neither he himself nor his fellows can estimate. It is the unique quality of rational beings that in great things and in small things they act from ideas. The magic power of thought cannot be exaggerated. Great conceptions have great consequences, and they rule the world. A new spiritual idea shoots forth its rays and enlightens to larger issues generations of men. There is a mystery in every forth-putting of will-power, and every expression of personality. Character cannot be computed. The art of goodness, of living nobly, if so unconscious a thing may be called an art, is one certainly which defies complete scientific treatment. It is with facts like these that Ethics has to do; and while we may lay down broad general principles which must underlie the teaching of every true prophet and the conduct of every good man, there will always be an element with which science cannot cope. IV. It will not be necessary, after what has been said, to trace at any length the relations between Ethics and the {15} special mental sciences, such as Logic, Aesthetics, and Politics.