phone; when photography is at the service of all classes; and when the latest fruit of the association of science and art, electro-technics, is opening to man, in its rapid unfolding, ever-new regions of inconceivable extent for further research and useful applications of the forces of Nature? To the investigator—who, more than any other class of men, is accustomed to draw conclusions from the course of observed phenomena as to the law controlling them—it is, however, not the latest state of development, but its causes, and the laws on which they depend, that are of surpassing importance. The clearly recognizable law is that of the progressive acceleration of our present advance in civilization. Periods of development, which in former times required hundreds of years for their accomplishment, which in the beginning of our age needed decades, are now completed in years, and sometimes come into being in full perfection. This is the natural result of our highly perfected system of instruction, by which the acquisitions of science, and particularly the scientific method, have been introduced into the broad stream of art and popular life in all their forms of efficacy.
Thus we see how, by virtue of our now excellent system of communications, every new scientific thought is at once flashed through the whole civilized world, and how thousands endeavor to grasp it and to apply it in the most diverse spheres of life. Sometimes it may be only modest observations, sometimes only the overcoming of small impediments that stand in the way of the recognition of the scientific relations of phenomena. They may often be the point of departure for a new course of advance, previously quite unanticipated, but important for human life. The progressive development conditioned upon these principles will therefore continue, if man does not himself in his conceit interrupt it, as long as science keeps going on to higher degrees of knowledge. The deeper insight we get into the secret processes of Nature, the more we are convinced that we are still standing in the extreme outer court of science, that an as yet immeasurable field of work lies before us, and that it still appears at least very questionable whether man will ever reach a complete knowledge of Nature. There is, therefore, no ground for doubting the continuance of the progressive ascent of scientific and technical evolution, unless man himself interferes with it by conduct inimical to civilization. But even hostile attacks can henceforth cause only temporary interruptions in the course of development, or at most only partial reversions, for, in the presence of the printing of books and the wide diffusion of the results of modern civilization, the scientific and technical accomplishments of mankind can never again be lost. Moreover, the peoples who cultivate these arts and lift them higher acquire through them such a dominant ascendency, so great a fullness of power, that their subjection in the contest with uncivilized people, and the breaking out of a new barbaric age, appear impossible.
While we thus regard the present development of civilization as
