a means of knowing how they will act on the human organism, and how that organism may react on them in the interest of its own life. The prejudice done by implicit reliance on sense testimony arose out of the fact that it presented objects as largely unrelated to each other--as so much being, rather than as so much doing, acting and interacting, determining and interdetermining. It became the function of reason to develop, out of the material furnished by the senses, a knowledge of the true nature of the system external to man and involving him in its scope which we call universe. In the carrying out of this function the analogical process has remained, but the analogies utilized, from being likenesses between what things seem to be to the senses, have more and more become analogies between propositions made regarding what things do, regarding how things act upon, are related to and determine each other. Our knowledge of Nature, therefore, illustrates progress from a stage in which external objects are viewed as so much doing--from a stage in which they seem more or less isolated, more or less independent of each other--to a stage in which we know them as acting and interacting, and therefore, by virtue of this action and interaction, as interrelated and interdependent. It was because man had to begin with the thought of the world around him as a series of unconnected aspects that he fell into the error of regarding every object as containing within itself the powers which it put forth; it was by gradually progressing to the knowledge of the external system as a process that he discovered how inextricably the smallest "flower in the crannied wall" is linked to its vastest environment, and how dependent must be the mechanism of the molecule, as well as of the solar system, upon the whole universe Power which we call cosmos.