CHAPTER I. 



INTRODUCTORY. 1 



Progress in science is better indicated by the viewpoints we attain than by- 

 massive accumulation of facts. Darwin's perspective made him a prodigy in the 

 assimilation of facts and an easy victor in the greatest conflict that science has 

 thus far had to meet. His triumph has won for us a common height from which 

 we see the whole world of living beings as well as all inorganic nature; phenomena 

 of every order we now regard as expressions of natural causes. The supernatural 

 has no longer a standing in science; it has vanished like a dream, and the halls 

 consecrated to its thraldom of the intellect are becoming radiant with a more cheer- 

 ful faith. 



In no other field of science is the viewpoint of such ever-present importance as 

 in biology. It means orientation of the field, clear vision in directing research, and 

 insight in the interpretation of phenomena. It may be well, therefore, to prepare 

 the ground a little in advance of the facts to be presented, and this can be done to 

 best advantage by taking our bearings from two of our foremost guides — Darwin 

 and de Vries. 



The great problem in biology, as it presented itself to these leaders, was to 

 account for progressive evolution by natural means. Supernaturalism had declared 

 the living world a stupendous miracle, a creation by fiat. Science had already made 

 good its claim to the physical world, but the animate sphere was still supposed to 

 rise supreme above natural law. Darwin was taught the creation dogma, and all 

 through the memorable voyage of the Beagle he was predisposed to regard species 

 as immutable. He stated in a letter to Dr. Otto Zacharias, in 1877 : 2 



When I was on board the Beagle I believed in the permanence of species, but, as far 

 as I can remember, vague doubts occasionally flitted across my mind. On my return home 

 in the autumn of 1836, I immediately began to prepare my journal for publication, and 

 then saw how many facts indicated the common descent of species, so that in July, 1837, 

 I opened a note-book to record any facts which might bear on the question. But I did not 

 become convinced that species were mutable until, I think, two or three years had elapsed. 



The five-year voyage on the Beagle, during which facts were collected with no 

 definite theory but with a haunting doubt as to the immutability of species, was 

 the foundation or germ-stage in the development of Darwin's great generalization. 

 It is still a notable fact that the germ of Darwin's views at this inceptional stage 

 was already a logical whole so far as fundamentals were concerned. The problem 

 embraced the entire organic kingdom, from lowest to highest. 



The great difficulty, then, was to find out how nature could be self-regulating 

 in bringing forth such nice adaptations as are everywhere patent in the organic 



1 The manuscript here selected as introductory to this volume was written in 1909, and formed part of a lecture 

 at Clark University, entitled "A study in evolution, based on color-characters in pigeons, and bearing on moot ques- 

 tions." A few phrases of that address are omitted. The data presented in connection with this lecture were not 

 reduced to writing, but accompanying lists of topics, illustrations, etc., show that many of the subjects which are fully 

 treated in the several chapters of this volume were diseased. — Editor. 



' Cited by Huxley in his Darwiniana Essays, p. 276. 



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