AGASSIZ AND EVOLUTION. 25 



tion ; the latter must follow the former, and constitute its completion. 

 The change from the one to the other is always attended with prodi- 

 gious impulse to science. 



To illustrate : Until Kepler, astronomy was little more than an 

 accumulation of disconnected facts concerning celestial motions — 

 abundant materials, but no science ; piles of brick and stone, but no 

 building. Kepler reduced this chaos to beautiful order and musical 

 harmony by the discovery of the three great laws which bear his name, 

 and therefore he has been justly called the legislator of the heavens — 

 the laiogiver of space. But, had he been asted the cause of these beau- 

 tiful laws, he could only have answered, " The^rs^ cause — the direct 

 will of the Deity." A good answer and a true, but not scientific ; be- 

 cause it places the question beyond the domain of science, which deals 

 only with second or physical causes. But Newton comes forward and 

 gives a physical cause. He shows that all these beautiful laws are the 

 necessary result of gravitation ; and thus astronomy becomes a phys- 

 ical science. So, until Agassiz, the facts of geological succession of 

 organic forms were in a state of lawless confusion. Agassiz by estab- 

 lishing the three great laws of succession, which ought to bear his 

 name, reduced this chaos to order and beauty ; and, therefore, he 

 might justly be called the legislator of geological liistory — the laxo- 

 giver of time. But, when asked the cause of these laws, he could only 

 answer, and did indeed answer, " The plans of the Creator." A noble 

 answer and true, but not scientific. Darwin now comes forward and 

 gives, partly at least, the cause of these laws. He shows that all these 

 beautiful laws are explained by the doctrine of " origin of species 

 by derivation with modifications " ; that these laws are not ultimate, 

 but derivative from more fundamental laws of life ; and thus biology 

 is advanced one step, at least, toward the causal stage. Newton and 

 Darwin substituted second causes for first cause — natural for super- 

 natural. They each in his own department broke the bonds of super- 

 naturalism in the domain of Nature. 



One more important reflection ; There are two, and only two, fun- 

 damental conditions of material existence — space and time. There 

 are, therefore, two, and only two, cosmoses — space-cosmos and time- 

 cosmos. These have been redeemed from confusion and reduced to 

 law and order and beauty — changed from chaos to cosmos — by science. 

 For this result we are chiefly indebted, in the one case, to Kepler and 

 Newton ; in the other, to Agassiz and Darwin. The universal law, in 

 the one cosmos, is the lato of gravitation ; in the other, the laic of 

 evolution. Traced by analysis to its deepest roots of philosophic truth, 

 the one law may be called the divine mode of sustentation ; the other, 

 the divine process of creation. 



Or, again : we have all heard of the " music of the spheres " — 

 a beautiful and significant name used by the old thinkers for the di- 

 vine order of the universe — a music heard not by human ear, but only 



