6 ETHICAL ASPECTS OF EVOLUTION 



and of the practical importance of the conclusions which 

 might be drawn from it ; it was seldom wholly absent 

 from my thoughts, and I was determined that, as soon as 

 circumstances were favourable, I would take it up again. 

 The task, which I resumed in 1897, after an interval of 

 thirty years, was this : to deduce a systematic explanation 

 of human conduct from premisses which were neither 

 optimist nor pessimist, but indifferent. The unifying 

 principle of which I was in search did not occur to me 

 till early in 1906. It is this : that though men s actions 

 may be determined sometimes in the direction of progress, 

 and at others in the direction of decay, the sole determinant 

 of their valuations is sympathy with the process of develop 

 ment, or forward evolution. 



The first lesson to be gained from a study of biological 

 change is that it does not always follow the same direction. 

 The immense progress which may be observed when the 

 lowest forms of life are compared with the highest has not 

 been obtained by a uniform advance along every channel 

 in which change has run. In countless instances the pro 

 cess has been abruptly broken off by the extinction of the 

 species. Where the species has survived, the change has 

 been sometimes in the direction of increased complexity, 

 in others, of simplification ; and in innumerable instances 

 the principle of evolution, after having effected only a very 

 low grade of differentiation, does not appear to have asserted 

 itself further ; or the change, when it occurs, has been in 

 details which do not involve either simplification or in 

 creased complexity of structure. For races which have 

 attained a high degree of differentiation there may be, so 

 far as the future can be predicted from the past, three 

 possible futures; either destruction, or continued growth 

 in complexity, or simplification contrasted processes which 

 may also be distinguished as development and degeneration. 

 For mankind as a whole, the escape, except by extinction, 

 from the alternative processes of evolutionary change, and 

 the acquisition of permanently stationary conditions, is too 

 purely speculative a conception to call for discussion. The 



