scientific method has been recognized, by the experience of ages that have passed as by that of present ages, as the only efficacious method of arriving at knowledge. This is the significance of the exclusion of mystery in the study of man and the universe, and in the government of individuals and societies, which is, or rather ought to be, the consequence of this study. The mystic who assumes to direct his life and business according to the ideas of the marvelous would very soon be lost; general history and mental pathology show that peoples and persons who have adopted mystery and divine inspiration as exclusive guides have been precipitated at once into irreparable moral, mental, and material ruin. We may, then, leave the mystics to enjoy their dreams, but must not permit their intolerance to impose these dreams upon us as the rule of social activity. Man has, indeed, always sought to escape the severity of determinism in this way, just as he formerly tried to impose his will upon the superior powers by the conjurations of magic, or to turn aside the rigor of destiny by incoherent prayers. But such illusions need not make us depart from the rigor of our method of proceeding, or be allowed, by an irrational confusion, to destroy the exactness of our results. This irrevocable separation between the scientific method and mystery has not always been; it is the product of a long elaboration, in which empirical and experimental conceptions have been associated and confounded. For better comprehension, let us try to summarize in general outline the historical evolution of science. In all things we can best comprehend the present by going back to the beginning.
Let us carry ourselves back to those distant periods during which our species was gradually disengaging itself from animality. We can do this to a certain extent by the aid of archæological discoveries, and by comparing them with the stories of travelers who have observed savage tribes which have been arrested at different steps of the evolution that has been accomplished since the primitive ages by civilized peoples. Thorough examination of the habits and instincts of animal species, knowledge of the laws of the psychological and physiological development of the individual, especially in his infancy, unite with history to cast a strong light on the problems with which we are here concerned. The sum of these studies has shown how the human races, each according to its degree of intelligence, have gradually created the instruments, arms, and customs by the aid of which they achieved their first triumphs over Nature and accomplished their first organizations. The family and the state, morality and virtue, gradually issued from the social instincts which we see in action, now, as formerly, among the animal races.
The intelligence of the first men was too feeble, however, to conceive either the abstract laws of their own development or those of
