The best books I know for the sweeping out of metaphysical cobwebs are "The Philosophy of Common Sense" and "The Creed of a Layman," by Frederic Harrison, leader of the English Positivists, a school of thought established by Auguste Comte. But even as I recommend these books, I recall the dissatisfaction with which I left them; for it appears that the Positivists have their dogmas like all the rest. Mr. Harrison is not content to say that mankind has not the mental tools for dealing with ultimate realities; he must needs prove that mankind never will and never can have these tools, I look back upon the long process of evolution and ask myself, What would an oyster think about Positivism? What would be the opinion of, let us say, a young turnip on the subject of Mr. Frederic Harrison's thesis? It may well be that the difference between a turnip and Mr. Harrison is not so great as will be the difference between Mr. Harrison and that super-race which some day takes possession of the earth and of all the universe. It does not seem to me good science or good sense to dogmatize about what this race will know, or what will be its tools of thought. What does seem to me good science and good sense is to take the tools which we now possess and use them to their utmost capacity. What is it that we know about life? We know a seemingly endless stream of sensations which manifest themselves in certain ways, and seem to inhere in what we call things and beings. We observe incessant change in all these phenomena, and we examine these changes and discover their ways. The ways seem to be invariable; so completely so that for practical purposes we assume them to be invariable, and base all our calculations and actions upon this assumption. Manifestly, we could not live otherwise, and the spread of scientific knowledge is the further tracing out of such "laws"--that is to say, the ways of behaving of existence--and the extending of our belief in their invariability to wider and wider fields. Once upon a time we were told that "the wind bloweth where it listeth." But now we are quite certain that there are causes for the blowing of the wind, and when our researches have been carried far enough, we shall be able to account for and to predict every smallest breath of air. Once we were told that dreams came from a supernatural world; but now we are beginning to analyze dreams, and to explain what they come from and what they mean. Perhaps we still find human nature a bewildering and unaccountable thing; but some day we shall know enough of man's body and his mind, his past and his present, to be able to explain human nature and to produce it at will, precisely as today we produce certain reactions in our test-tubes, and do it so invariably that the most cautious financier will invest tens of millions of dollars in a process, and never once reflect that he is putting too much trust in the permanence of nature.