planets to follow; he made velocity increase proportionally to the time in falling bodies; he made the laws of the sines for light to obey when refracted; he established the classes, orders, families and genera of plants and animals, and fixed the distances between them. He thought the archetypes of all things, and devised their variations; and when we re-discover any one of these his wondrous institutions, we seize his mind in its very literal intention.
But as the sciences have developed farther, the notion has gained ground that most, perhaps all, of our laws are only approximations. The laws themselves, moreover, have grown so numerous that there is no counting them; and so many rival formulations are proposed in all the branches of science that investigators have become accustomed to the notion that no theory is absolutely a transcript of reality, but that any one of them may from some point of view be useful. Their great use is to summarize old facts and to lead to new ones. They are only a man-made language, a conceptual shorthand, as Pearson calls them, in which we write our reports of nature; and languages, as is well known, tolerate much choice of expression and many dialects.
Thus human arbitrariness has driven divine necessity from scientific logic. If I mention the names of Sigwart, Mach, Ostwald, Pearson, Milhaud, Poincaré, Duhem, Heymans, those of you who are students will easily identify the tendency I speak of, and will think of additional names.
Riding now on the front of this wave of scientific logic Messrs. Schiller and Dewey appear with their pragmatistic account of what truth everywhere signifies. Everywhere, these men say, 'truth' in our ideas and beliefs means the same thing that it means in science. It means, they suggest, nothing but this, that ideas become true just in so far as they help us to get into satisfactory relation with the other parts of our experience, to synthesize and summarize facts and other ideas, and get about among them by conceptual short-cuts instead of following the interminable labyrinth of particular phenomena as they succeed one another. Any idea upon which we can ride, so to speak; any idea that will carry us prosperously from any one part of our experience to any other part; linking things satisfactorily, working securely, simplifying, saving labor, is true for just so much, true in so far forth, true instrumentally. This is the 'instrumental' view of truth taught so successfully at Chicago, the view that truth means the power of our ideas to 'work,' promulgated so brilliantly at Oxford.
Messrs. Dewey, Schiller and their allies, in reaching this general notion of all truth, have only followed the example of geologists, biologists and philologists. In the establishment of these other sciences, the successful stroke was always to take some simple process actually observable in operation—as denudation by weather, say, or