ADDRESS. 7 
ideas, parallel to those which have done so much towards elucidating the 
problems of life, hold good also in the world of matter ; and I believe that 
it will be possible to show that in this respect there exists a resemblance 
between the two realms of nature, which is not merely fanciful. It is 
proper to add that as long ago as 1873 Baron Karl du Prel discussed the 
same subject, from a similar point of view, in a book entitled ‘The Struggle 
for Life in the Heavens.’ ! 
Although inanimate matter moves under the action of forces which 
are incomparably simpler than those governing living beings, yet the 
problems of the physicist and the astronomer are scarcely less complex 
than those which present themselves to the biologist. The mystery of 
life remains as impenetrable as ever, and in his evolutionary speculations 
the biologist does not attempt to explain life itself, but, adopting as his 
unit the animal as a whole, discusses its relationships to other animals 
and to the surrounding conditions. The physicist, on the other hand, is 
irresistibly impelled to form theories as to the intimate constitution of the 
ultimate parts of matter, and he desires further to piece together the past 
histories and the future fates of planets, stars, and nebule. If then the 
speculations of the physicist seem in some respects less advanced than 
those of the biologist, it is chiefly because he is more ambitious in his 
aims. Physicists and astronomers have not yet found their Johannesburg 
or Kimberley ; but althcugh we are still mere prospectors, I am proposing 
to show you some of the dust and diamonds which we have already 
extracted from our surface mines. 
The fundamental idea in the theory of Natural Selection is the 
persistence of those types of life which are adapted to their surrounding 
conditions, and the elimination by extermination of ill-adapted types. 
The struggle for life amongst forms possessing a greater or less degree of 
adaptation to slowly varying conditions is held to explain the gradual 
transmutation of species. Although a different phraseology is used when 
we speak of the physical world, yet the idea is essentially the same. 
The point of view from which I wish you to consider the phenomena, of 
the world of matter may be best explained if, in the first instance, I 
refer to political institutions, because we all understand, or fancy we 
understand, something of politics, whilst the problems of physics are 
commonly far less familiar to us. This illustration will have a further 
advantage in that it will not be a mere parable, but will involve the 
fundamental conception of the nature of evolution. 
The complex interactions of man with man in a community are usually 
described by such comprehensive terms as the State, the Commonwealth, 
or the Government. Various States differ widely in their constitution 
and in the degree of the complexity of their organisation, and we classify 
them by various general terms, such as autocracy, aristocracy, or de- 
mocracy, which express somewhat loosely their leading characteristics. 
* Der Kampf um’s Dasein am Himmel (zweite Auflage), Denicke, Berlin, 1876. 
