precedes the effect in time, it is evident that the proof is 
     not essentially affected. Moreover, the argument does not 
     require that all chains of causation, when traced 
     backward, should terminate on the same  ultimate point: 
     in other words, it does not lead necessarily to the 
     conclusion that the universe acquired its entire stock-in-
     trade in a single consignment at the Creation, and that it 
     has received nothing since. Thus it does not warrant the 
     view, so common among the deistic Newtonians of the 
     eighteenth century, that the system of the world is 
     absolutely closed and has developed according to purely 
     mechanical laws, so that all the events of history must 
     have been implicit in its specification at the primeval 
     instant. On the contrary, the recent trend of physical 
     thought (as will be evident from what has been said 
     about the principle of causality) is in favor of the view