Dr. Tyndall stands as one of the most popular exponents of scientific knowledge, and may be regarded as a fair representative of the feelings of many scientific men. And in his estimation "the problem of problems of our day is to find a legitimate satisfaction for the religious emotions." He admits that these religious emotions are inexpugnable facts of human nature, as certain and as incontestable as the facts of physics. Now what is meant by a _legitimate_ satisfaction of the religious emotions? Does it not mean that human reverence must have a _real_ and a worthy Object? that for human duty there must be an imperative ground of obligation? that for true loyalty of soul to truth and right there must be an eternal reason? and that the instinctive trust of the soul in everlasting righteousness and everlasting love must have a rational vindication? Where shall we look for this object? "May we look upward and onward, or have we nothing to do but yield to the pressure from behind and below?" What conception are we to form of that mysterious Power or Principle which stands in necessary correlation with the religious nature of man? Dr. Tyndall permits us "to fashion this conception as we will"--with that "he has nothing to do;" only he demands that in doing so we observe two conditions: 1. "Be careful that your conception is not an unworthy one;" "invest it with your highest and holiest thoughts." 2. Allow "no intrusion of purely creative power into any series of phenomena," no arbitrary interference with the order of nature "for special purposes." The first condition would be violated by our conceiving that Power as purely _mechanical_, for then the sublimest interests of our moral and spiritual life would be surrendered to the action of the same force as that which draws a stone to the earth. The conception of unconscious and unmoral force is not our highest and holiest thought--it can not inspire reverence and loyalty and love. The second condition would be violated by our regarding that Power as _arbitrary_--that is, as following no law; for that would be opposed to all the inductions of modern science, and would invalidate all conclusions based on the assumed permanence of natural laws. The problem, then, is to steer between the Scylla and Charybdis of mechanism and arbitrariness, and find the open sea where freedom may move in harmony with law, and where, in the grand hierarchy of laws the physical order of the world may be co-ordinated with, perhaps subordinated to, the higher reign of righteousness and love.