SUMMARY OF FOUR CENTURIES OF SCIENCE. 271 



by every man of science, insisted upon and often recom- 

 mended by them to their disciples. 5. The XVIth century 

 is marked by another character which clearly makes its 

 appearance in the European world for the first time 

 namely, the discovery of the existence of NATURAL LAWS 

 the recognition of which is a fact of the highest import, 

 for it will end in gradually altering the spiritual, and the 

 temporal, world. To sum up, then, this century is marked 

 by discoveries of the first order and the foundation of 

 the sciences ; spirit of free inquiry ; experimental work ; 

 the working and formulation of the inductive process ; the 

 recognition of natural laws. These are the five features 

 of the modern world, for the following ages, while striking 

 out new roads in unbeaten fields, accentuate these features 

 more and more, without, however, altering their nature, 

 so truly and unmistakably was the XVIth century an age 

 of real science a fact which is unanswerably demonstrated 

 by its work. 



II. Constitution. In many respects the XVIth century 

 is grander altogether than the following age. Its startling 

 discoveries, its varied revolutionary movements, naturally 

 strike the imagination far more deeply. The Reforma- 

 tion, which is the main expression of the energetic spirit 

 of the period, would be sufficient to make it a colossal 

 century. Yet the XVI Ith century is, scientifically, more 

 imposing. If it is less original and versatile, it is also 

 less tentative and more sterling. The feature which dis- 

 tinguishes it strongly is the discovery of GRAND LAWS, and 

 the extremely rapid development of four branches astro- 

 nomy, mathematics, physics, and physiology. The march 

 in these is the same as in the XVIth century. Facts are 

 first collected with patient and untiring labour, then laws are 

 determined after careful experimentation, i. ASTRONOMY 

 enters a new stage. The telescope has revealed a universe 

 undreamt-of, and from this fact two consequences ensue : 

 the Copernican system is proved to be true, and authority 

 receives its death-blow, although it will die hard, and 

 during its agony exercise its might with desperate cruelty 

 for a time. 2. MATHEMATICS also enter a new era. Des- 



