a law and the popular mind will soon vaguely conceive it as a rule or uniformity resulting from some kind of unconscious will-power at the back of everything; and this Will-Power stops the gap created in our thought by the exclusion of theism and finality. This confusion is furthered still more by not distinguishing between the cause of a fact and the cause of our knowledge of the fact. If I act in willing conformity with the civil law, I also act in obedience to it, in some way coerced by its authority and its sanctions. The law is really a cause of my action; because it represents the fixed will and effectual power of the ruler. But when this conception and name is transferred by analogy to physical uniformities of action, an event which conforms to the observed law or regularity of sequence, is not really caused by the law unless we suppose that law to be representative of something equivalent to a fixed will from which it originates. Yet we say loosely, such an event happens _in consequence of_ the law of attraction; meaning only, _in conformity with_ the law, so as to verify the law, to follow from it logically. Thus again the law comes to be mistaken for an effectual power of some kind, whereas it is merely a sort of regularity that might result either from an intelligent will or from something equivalent. But in thus adroitly slipping-in the conception of a governing force or tendency, or even in openly asserting it, with Schopenhauer or Hartmann, and in explaining the graduated resemblances of species by the origin of one from the other, and in extending this mode of Evolution in all directions from the known to the unknown so as to make it pervade the universe, we at once cease to be faithful positivists and, becoming philosophers, must submit to philosophic criticism, since these problems cannot be settled merely by an appeal to facts. Thus when Professor Mivart speaks of Evolution as "the continuous progress of the material universe by the unfolding of latent potentialities in harmony with a preordained end," the latent potentialities, the preordained end, the procession of one species from another, the extension of this law to every difference of time and place--all are matters of hypothesis or intuition; but by no means of exterior observation.