THE VALUE OF LI FE 



(provokin.iT adaptation) determinc(L We cannot admit 

 any conscious direction to a certain end, either in the 

 form of theistic predestination or pantheistic fmahty. 

 For this we must substitute a simi)le mechanical causahty 

 in the sense of psycho-mechanical monism or hylozoism. 



Although the stem-history of i)lants and animals, like 

 the history of humanity, shows a progressive advance 

 taken as a whole, we find a good deal of vacillation in 

 detail. These historical waves are wholly irregular; in 

 periods of decay the hollows of the waves often persist 

 for a long time, and are then succeeded by a fresh rise 

 to the crest of another wave. New and rapidly advanc- 

 ing groups come to take the place of the old decaying 

 groups, bringing with them a higher stage of organiza- 

 tion. Thus, for instance, the ferns of to-day are only a 

 feeble survival of the huge and varied pteridophyta that 

 formed the most conspicuous part of the paleozoic 

 forests in the Devonian and Carboniferous periods ; they 

 were ousted in the Secondary Period by their gymno- 

 sperm descendants (cycadea and conifers), and these, 

 again, in the Tertiary Period by the angiosperm flowering 

 plants. So among the terrestrial reptiles the modern 

 tortoises, serpents, crocodiles, and lizards are only a 

 feeble remnant of the enormous reptile-fauna that 

 dominated the Secondary Period, the colossal dinosauri, 

 pterosauri, ichtyosauri, and plesiosauri. They were 

 replaced in the Tertiary Period by the smaller but more 

 powerful mammals. In the history of civilization the 

 Middle Ages form a deep valley between the crests of 

 the waves of classical antiquity and modern culture. 



These few examples suffice to show that the various 

 classes and orders of living things have a very different 

 value when comy)ared with each other. In regard to 

 their intrinsic aim, self -maintenance, it is true that all 

 organisms are on a level, but in their relations to other 

 living things and to nature as a whole thev are of very 



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