MODERN THOUGHT 137 



his theory of values, while phrases like Natural Selection and the doc- 

 trine of evolution recall Darwin and Spencer. Words and phrases alike 

 point to a struggle for condensation of thought in terms so clear and 

 simple that no one can mistake their meaning. 



Inasmuch as science has become international and we no longer 

 speak of it as French, English or German, but simply as science, some- 

 thing in which all seekers after truth have a common ownership, a few 

 of those explanations of the universe may now be considered which 

 " exact thought " has given. We may look first of all at the abstract 

 views, four in number, which are ancient in their origin, mathematical 

 in their form and are still ardently defended. These are what have 

 been termed the astronomical view of the world, the atomic view, the 

 kinetic view and the physical view. The latter is the explanation 

 given by those who believe in energy as the underlying and directing 

 cause of movements or changes in the universe. 



The astronomical theory rests on the doctrine of gravitation and 

 explains the phenomena of the world in which we live as well as the 

 relation and movements of the heavenly bodies to each other by the 

 assumption of its universal existence. Upon the principle that bodies 

 attract each other directly as their mass, inversely as the square of their 

 distance, Newton enunciated his law of falling bodies. Upon this same 

 principle the tides were explained as well as the revolution of the earth 

 on its own axis and round the sun, the rotation of the heavenly bodies 

 around their axes and around the sun, their motion through space and 

 the velocity of this motion. If gravitation is universally operative on 

 the earth, why should it not be operative everywhere ? Through aid of 

 the calculus Newton was able to apply the law of gravitation with the 

 utmost accuracy and by its application lay bare the secrets of the 

 heavenly bodies. 



Newton's principles were received more favorably in France than 

 in England. Under the influence of Laplace and the Paris Academy 

 of Sciences, in spite of the protest of a sceptic here and there these 

 principles were, after thorough and somewhat bitter discussion, accepted 

 as true in France, and in no long time in all Europe. On Newton's 

 theory of gravity, the corpuscular explanation of light made its way in 

 scientific circles. Light was believed to be a substance and its laws of 

 reflection and refraction were explained by the law of falling bodies. 



The discovery of magnetism in 1791, of the voltaic pile in 1800, and 

 researches into the phenomena of electricity, together with a growing 

 conviction that space is empty and that matter is composed of atoms 

 and requires a void, weakened confidence in the astronomical theory as 

 a full and satisfactory explanation of all the phenomena of the universe. 

 No one denied the facts which Newton had brought forward. No one 

 ventured to assert that gravitation does not act everywhere, or that its 



VOL. LXXXI. — 10. 



