1 82 THE HISTORY OF CKEATION. 



manner talents for special mental activities are transmitted in 

 many families for generations, as, for instance, talent for 

 mathematics, poetry, music, sculpture, the investigation of 

 natm-e, philosophy, etc. In the family of Bach there have 

 been no less than twenty-two eminent musicians. Of course 

 the transmission of such peculiarities of mind depends upon 

 the material process of reproduction, as does the transmission 

 of mental qualities in general. In this case again, the vital 

 phenomenon, the manifestation of force (as everywhere in 

 nature), is directly connected with definite relations in the 

 admixture of the material components of the organism. It 

 is this definite proportion and molecular motion of matter 

 which is transmitted by generation. 



Now, before we examine the numerous, and in some cases 

 most interesting and important, laws of transmission by 

 inheritance, let us make ourselves acquainted with the 

 actual nature of the process. The phenomena of transmis- 

 sion by inheritance are generally looked upon as something 

 quite mysterious, as peculiar processes which cannot be 

 fathomed by natural science, and the causes and actual 

 nature of which cannot be understood. It is precisely in 

 such a case that people very generally assume supernatural 

 influences. But even in the present state of our physiology 

 it can be proved with complete certainty that all the 

 phenomena of inheritance are entirely natural processes, 

 that they are produced by mechanical causes, and that they 

 depend on the material phenomena of motion in the bodies 

 of organisms, which we may consider as a part of the 

 phenomena of propagation. All the phenomena of Heredity 

 and the laws of Transmission by Inheritance can be traced 

 to the material process oi Propagation. 



