DARWINISM AND EVOLUTION DEFINED. 13 



.-are ever to be associated with the theory of over-production, 

 struggle, and selection. 



Darwinism may be defined, then, as a certain rational, 



causo-mechanical (hence, non-teleologic) explanation of the 



The Bar- origin of new species. The Darwinian explana- 



MtioTo^de-" ^ on rests on certain observed facts, and certain 

 scent, inductions from these facts. The observed 



facts are : ( i ) the increase by multiplication in geometrical 

 ratio of the individuals in every species, whatever the kind 

 of reproduction which may be peculiar to each species, 

 whether this be simple division, sporulation, budding, par- 

 thenogenesis, conjugation and subsequent division, or 

 -amphimixis (sexual reproduction) ; (2) the always apparent 

 slight (to greater) variation in form and function existing 

 among all individuals even though of the same generation or 

 brood; and (3) the transmission, with these inevitable 

 slight variations, by the parent to its offspring of a form 

 and physiology essentially like the parental. The inferred 

 (also partly observed) facts are: (i) a lack of room and 

 food for all these new individuals produced by geometrical 

 multiplication and consequently a competition (active or 

 passive) among those individuals having any cecologic rela- 

 tions to one another, as, for example, among those occupying 

 the same locality, or needing the sarne food, or needing each 

 other as food; (2) the probable success in this competition 

 of those individuals whose slight differences (variations) 

 are of such a nature as to give them an advantage over their 

 confreres, which results in saving their life, at least until 

 they have produced offspring; and (3) the fact that these 

 "saved" individuals will, by virtue of the already referred 

 to action of heredity, hand down to the offspring their 

 advantageous condition of structure and physiology (at 

 least as the "mode" or most abundantly represented condi- 

 tion, among the offspring). 



The competition among individuals and kinds (species) 



