the criterion to which every idea or judgment is subjected. All that upholds the established authority is good, and therefore true; all that tends to weaken it is bad and therefore false. The primary purpose of intelligence is thus diverted and frustrated.
The essential characteristic of scientific technique is that it proceeds from experiment, and demands objective criteria. Science believes in salvation, not by faith but by verification. To practice it we must subordinate all other motives and whatever may have meant most to us to the love of the truth; and "we shall find truth only upon that wide-open but almost untraveled road which leads away from ourselves." Love of truth, without passion or prejudice or predilection, is the first principle in the ethical code of scientists, one of whom has recently said that the Decalogue of Moses might be accepted as the Decalogue of Science if the word "Truth" were substituted for the word "God." All the progress we have won has depended upon truth, and the acquisition of this truth upon intellectual honesty.
For ages the idea of truth in common thought has been that of something absolute and final, "a light planted in eternal principles and shining upon our path." Every such idea of absolute truth, however, has failed in some phase in the test of new knowledge and progressive living. In contrast with this way of thinking, to the scientist what is regarded as truth at any particular time is not likely to be final. The best a finite mind can achieve is but a dim outlining of what may be in a final cast of thought the ultimate in the relations of reality and mind. "Truths emerge from facts, but they dip forward into facts again and add to them, which facts again create or reveal new truth." What we call natural laws tersely summarize our experience of the world at a given time and endow us with a gift of prophecy that points the way to new advances.
Difficulties are to science the stepping stones to higher ground. When it was found that Uranus did not follow the calculated orbit, the result was not abandonment of the theory of gravitation, but the discovery of Neptune. When it was found that nitrogen prepared by different methods yielded different atomic weights, the outcome was not the breakdown of chemical theory, but the discovery of argon, and later, of isotopes, thereby increasing the range of chemical knowledge. Similarly today, the impossibility, by existing means, of measuring precisely at the same time both the position and the momentum of a particle within the atom,—designated as Heisenberg's principle of indeterminacy—is not a denial of causation but an opportunty for further research. Certainly the principle is no valid argument for freedom of the will in view of the fact it does not apply to molecules and aggregations of these of which living things are always composed. In the growth of real knowledge a contradiction is the first step toward a victory.
