COMPLICATED CONDITIONS. 257 
individuals, as of all other organisms, by far the majority 
perish at the earliest period of their lives. Of the im- 
mense quantity of germs which every species produce, only 
very few actually succeed in developing, and of these few 
it is again only a very small portion which attain to the age 
in which they can reproduce themselves (compare p. 161). 
From the disproportion between the immense excess of 
organic germs and the small number of chosen individuals 
which are actually able to continue in existence beside one 
another, there follows of necessity that universal struggle 
for life, that constant fight for existence, that perpetual com- 
petition for the necessaries of life, of which I gave a 
sketch in my seventh chapter. It is this struggle for life 
which brings natural selection into play, which in its 
turn is made use of by the interaction of the phenomena of 
Inheritance and Adaptation as a sifting agency, and which 
thus causes a continual change in all organic forms. In 
this struggle for acquiring the necessary conditions of 
existence, those individuals will always overpower their 
rivals who possess any individual privilege, any advan- 
tageous quality, of which their fellow competitors are 
destitute. It is true we are able only in the fewest 
cases (in those animals and plants best known to us) to 
form an approximate conception of the infinitely com- 
plicated interaction of the numerous circumstances, all 
of which here come into combination. Only think how 
infinitely varied and complicated are the relations of 
every single human being to the rest of mankind, and in 
general, to the whole of the surrounding outer world. But 
similar relations prevail also among all animals gnd plants 
which live together in one place. AI influence one another 
VOL, I. ; ) 
