by inheritance from prehistoric barbarians and savages, in whom the earliest religious ideas were wholly dominated by animism and fetichism. IV THE SCIENCE OF LIFE Object of biology--Relation to the other sciences--General and special biology--Natural philosophy--Monism: hylozoism, materialism, dynamism--Naturalism--Nature and spirit--Physics--Metaphysics--Dualism--Freedom and natural law--God in biology--Realism--Idealism--Branches of biology--Morphology and physiology--Anatomy and biogeny--Ergology and perilogy. The broad realm of science has been vastly extended in the course of the nineteenth century. Many new branches have established themselves independently; many new and most fruitful methods of research have been discovered, and have been applied with the greatest practical success in furthering the advance of modern thought. But this enormous expansion of the field of knowledge has its disadvantages. The extensive division of labor it has involved has led to the growth of a narrow specialism in many small sections; and in this way the natural connection of the various provinces of knowledge, and their relation to the comprehensive whole, have been partly or wholly lost sight of. The importation of new terms which are used in different senses by one-sided workers in the various fields of science has caused a good deal of misunderstanding and confusion. The vast structure of science tends more and more to become a tower of Babel, in the labyrinthic passages of which few are at their ease and few any longer understand the language of other workers. In these circumstances, it seems advisable, at the commencement of our philosophic study of "the wonders of life," to form a clear idea of our task. We must carefully define the place of biology among the sciences, and the relation of its various branches to each other and to the different systems of philosophy. In the broadest sense in which we can take it, biology is the whole study of organisms or living beings. Hence not only botany (the science of plants) and zoology (the science of animals), but also anthropology (the science of man), fall within its domain. We then contrast with it all the sciences which deal with inorganic or lifeless bodies, which we may collectively call abiology (or anorganology); to this belong astronomy, geology, mineralogy, hydrology, etc. This division of the two great branches of science does not seem difficult in view of the fact that the idea of life is sharply defined physiologically by its metabolism and chemically by its plasm; but when we come to study the question of abiogenesis (chapter xv.) we shall find that this division is not absolute, and that organic life has been evolved from inorganic nature. Moreover, biology and abiology are connected branches of cosmology, or the science of the world.