CHAPTER XLI
EUROPE OF TO-DAY
275. The scholars and learned men of the Middle Ages were but little interested in the world about them. They devoted far more attention to philosophy and theology than to what we should call the natural sciences. They were satisfied in the main to get their knowledge of nature from reading the works of the ancients, above all of Aristotle. Roger Bacon, as we have seen, protested against the exaggerated veneration for books. He foresaw that a careful examination of the things about us,—like water, air, light, animals and plants,—would lead to important and useful discoveries which would greatly benefit mankind.
Modern scientific methods of discovering truth.
Experimentation.
He advocated three methods of reaching truth which are now followed by all scientific men. In the first place, he proposed that natural objects and changes should be examined with great care, in order that the observer might determine exactly what happened in any given case. This has led in modern times to incredibly refined measurements and analysis. The chemist, for example, can now determine the exact nature and amount of every substance in a cup of impure water, which may appear perfectly limpid to the casual observer. Then, secondly, Roger Bacon advocated experimentation. He was not contented with mere observation of what actually happened, but tried new and artificial combinations and processes. Nowadays experimentation is constantly used by scientific investigators, and by means of it they discover many things which the most careful observation would never reveal. Thirdly, in order to carry on investigation and make careful measurements and the desired experiments, apparatus designed for the special purpose of discovering truth was necessary. As early as the thirteenth century it was found, for example, that a convex crystal or bit of glass would magnify objects, although several centuries elapsed before the microscope and telescope were devised.
Astrology grows into astronomy.
The progress of scientific discovery was hastened, strangely enough, by two grave misapprehensions. In the Middle Ages even the most intelligent believed that the heavenly bodies influenced the fate of mankind; consequently, that a careful observation of the position of the planets at the time of a child's birth would make it possible to forecast his life. In the same way important enterprises were only to be undertaken when the influence of the stars was auspicious. Physicians believed that the efficacy of their medicines depended upon the position of the planets. This whole subject of the influence of the stars upon human affairs was called astrology, and was in some cases taught in the mediæval universities. Those who examined the stars gradually came, however, to the conclusion that the movements of the planets had no effect upon humanity; but the facts which the astrologers had discovered through careful observation became the basis of modern astronomy.
Alchemy grows into chemistry.
In the same way chemistry developed out of the mediæval study of alchemy. The first experimentation with chemicals was carried on with the hope of producing gold by some happy combination of less valuable metals. But finally, after learning more about the nature of chemical compounds, it was discovered that gold was an element, or simple substance, and consequently could not be formed by combinations of other substances.