3i8 GREAT MEN OF SCIENCE 



suggested to Darwin the idea which showed the wonder of 

 the manifestations of Ufe as connected with the still greater 

 marvel of the coming into existence of life on this planet. 

 His idea made it seem possible that these marv^els could be 

 investigated by scientific methods, by methods therefore 

 which only strive after the determination of realities, and 

 which had already revealed so much that had appeared in- 

 comprehensible; though not, it is true, without having 

 shown behind every marvel thus explained a still greater 

 marvel, precisely in accordance with the position of man's 

 limited mind when confronted with the whole of nature. 



The course of applying scientific research to these wonders 

 of nature was followed by Darwin with great persistence, by 

 collecting an unheard-of mass of relevant facts which, when 

 properly arranged, all pointed in one direction. They ap- 

 peared to show that life on the earth had started from small 

 beginnings, and gradually developed in the course of the 

 long periods of time since the cooling of the earth's surface, 

 to ever higher forms and ever-increasing complexity; and 

 that this had occurred as the result of small variations ap- 

 pearing in the progeny of organisms, combined with the 

 effect of a continual selection of the fittest forms, namely 

 those forms best able to maintain themselves in the given 

 environment for further reproduction, and a continual des- 

 truction of unsuitable forms as a result of the perpetual 

 battle with the environment, which battle is actually a charac- 

 teristic of all development of life. This very general idea is 

 developed by Darwin in every direction in his book On the 

 Origin of Species, which appeared in 1859. On account of 

 the indefatigable way in which he investigated everything 

 that told for and against the idea, and estimated it solely 

 from the point of view of truth, and because the idea thus 

 connected with a large range of facts is correspondingly fruit- 

 ful, and has become of the highest value as regards further 

 progress in our knowledge of life, we have put forward 



