182 THE HISTORY OF CREATION. 
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 
nature, 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 T'ransmission by Inheritance can be traced 
to the material process of Propagation. 
