ERASMUS DARWIN. 147 



be too bold to imagine, in the great length of time since the 

 earth began to exist, perhaps millions of ages before the com- 

 mencement of the history of mankind, that all warm-blooded ani- 

 mals have arisen from one living filament, which the first great 

 Cause imbued with animality, with the power of acquiring new 

 parts, attended with new propensities, directed by irritations, sen- 

 sations, volitions, and associations, and thus possessing the faculty 

 of continuing to improve by its own inherent activity, and of de- 

 livering down those improvements by generation to posterity, world 

 without end ? " 



We must remember in reading this sentence that 

 by generation Darwin means inheritance, heredity 

 being a term which was introduced much later. If 

 we analyze this sentence, we see that it involves, 

 first, a clear idea of the evolution of all forms of 

 life from a single filament or minute organic mass, 

 as we should express it to-day, a minute mass of 

 protoplasm; second, that this evolution has occu- 

 pied millions of years and has been controlled not 

 by supernatural causes but by natural causes. The 

 directing power to which he alludes has sprung 

 from its efforts to meet its new needs in course of 

 its changing environment. For it is clear from the 

 context that by the term 'inherent activity,' Dar- 

 win does not allude to an automatic perfecting prin- 

 ciple such as we find originated with Aristotle, but 

 that the power of improvement rests with the ani- 

 mal's own efforts, the effects of these efforts upon 

 the body being transmitted. Darwin seems to feel 

 that he may be charged with irreverence in thus 

 substituting the idea of Evolution for that of Spec- 



