AND OF THE SECOND LAW 43 



formly in said system. In this aggregate aspect it is a 

 passage from variety to uniformity. 



(3) Net growth of entropy in all bodies participating in an 

 occurrence means that the system as a whole has experienced 

 an irreversible change of state. This change is of course 

 in harmony with the first law of energy, but this growth 

 gives additional information as it indicates the direction 

 in which a natural process occurs. 



(4) Growth of entropy is from less probable to more probable 

 states. 



Growth of entropy is passage to a state more greatly preferred 



by nature. 

 Growth of entropy is what obtains whenever a natural process 



occurs " spontaneously." 



{ unsettled 1 



Growth of entropy is a passage from \ , , . \ to more 



j^ less stable J 



f settled 1 



( stable J condltlons - 



All these statements are conspicuously based on the theory 

 of probabilities. 



(5) Growth of entropy is a passage from a somewhat regulated 

 to a less regulated state. It represents, in a certain sense, 

 Nature's escape from thralldom. 



Growth of entropy is a passage from a somewhat ordered 



to a less ordered molecular arrangement. 

 Growth of entropy is an increase in the disorder of a systerri 



of mass points. 

 Growth of entropy corresponds to an increase in the number 



of molecular complexions. 



(6) Finally we give a mathematical concept which covers 

 the whole domain of physics: "Any function whose time 

 variation always has the same sign until a certain state 

 is reached and is then zero, may be called an entropy 

 function." 



