10 HEREDITY AND SELECTION IN SOCIOLOGY 



most exalted object which we are capable of conceiving — namely, 

 the production of the higher animals — directly follows." ^ 



Darwin still accepted, though with considerable hesitation, 

 the Lamarckian theory of the transformation of organisms 

 through the use or disuse of their organs. But the arguments 

 of Weismann have shown us the fallacy of the Lamarckian 

 theory, and we are compelled, in the light of recent biological 

 research, to reject it. 



The conclusion which we reach as a result of the Darwinian 

 doctrine is that the co-operation of the four factors of variability, 

 heredity, excessive fecundity, and natural selection, results in 

 an ever greater perfection, in the form of an ever increasing 

 adaptation to surrounding conditions. This progression, how- 

 ever, is npt unconditional. We may divide the quaUty of 

 progeny into three classes. The first of these classes is com- 

 posed of those ofispring who are superior in organisation to the 

 parents ; the second consists of those who remain on the same 

 level with their parents ; while the third is composed of those 

 whose organisation is inferior, and marks retrogression. Should 

 the first two types exclusively be permitted to reproduce them- 

 selves, the level of the-species cannot fail to be raised in respect 

 of quality ; such is the case with all those species in which 

 natural selection has not been wholly or partially superseded by 

 a dominance of purely traditional factors. Should the third 

 type be allowed a share in the reproduction of the species equal 

 to the share of the two superior types, then a general retrogres- 

 sion and ultimate extinction of the species are inevitable. Man 

 has reached his level at the summit of the world of organic life, 

 thanks to the ceaseless and salutary process of natural selec- 

 tion. Should he persist in counteracting that natural selection 

 by creating artificial conditions of life, then retrogression is 

 inevitable, and the outcome of this is extinction. 

 * The Origin of Species, p. 669. 



