In those days when reflection had not set in,--when humanity had not yet found itself a stranger in the house of Nature, and had not yet dared to regard her as a mere automatic slave, men had no doubts as to the meaning of things. They lived sympathetically her life. 'Man, once descried, imprints for ever His presence on all lifeless things: the winds Are henceforth voices, wailing or a shout, A querulous mutter, or a quick gay laugh.' To the extent of his abilities and his culture, indeed man has in all ages read himself into the phenomena external to him. Such readings, in times when he feared and loved his kinsfolk of Nature, were fetichism and anthropomorphism. Gradually, however, forgetting his community, he claimed to be the measure and master of all things: to decree their use and function. But in course of time, when the sciences had emancipated themselves from the yoke of philosophy, they refused to borrow any such help in reading the riddle of the universe, and resolved to begin, _ab ovo_, from the atom or cell, and leave the elements to work out their own explanation. Modern science in so doing practises the lessons learned from Spinoza and Hume. The former teaches that all conception of order, i. e. of adaptation and harmony in nature, and indeed all the methods by which nature is popularly explained, are only modes of our emotional imagination, betraying how imperfect has been in most of us the emancipation of human intellect from the servitude to the affections[2]. The latter points out that all connexions between things are solely mental associations, ingrained habits of expectation, the work of time and custom, accredited only by experience[3]. There must be no pre-suppositions allowed in the studies of science, no help derived prematurely from the later terms in the process to elucidate the earlier. Let man, it is said, be explained by those laws, and by the action of those primary elements which build up every other part of nature: let molecules by mechanical union construct the thinking organism, and then construct society. The elements which we find by analysis must be all that is required to make the synthesis. Thus in modern times science carries out, fully and with the details of actual knowledge in several branches, the principles of the atom and the void, which Democritus suggested.