III. 



THE DOCTRINE OF IMMORTALITY. 



Your Royal Highnesses! 



To your Royal Highnesses I wish to express my profound 

 and respectful thanks for the honor of your presence, which 

 has for me a great and unforgetable significance. The partici- 

 pation of your Royal Highnesses in to-day's lecture is a high 

 distinction not only for me but for my university, which we 

 gratefully acknowledge. 



Everything living arises only from the living. The phe- 

 nomenon of propagation of animals and of plants has always 

 excited the interest of mankind. The ancients recognized 

 that only living parents could have a living progeny, and it 

 was said "Omne vivum ex vivo." But for a long time the 

 opinion prevailed that life might continually arise anew. We 

 know now, however, with certainty that a new generation of 

 this kind does not occur, and assume that under present con- 

 ditions a new generation of life is improbable, perhaps impos- 

 sible. We know too little to venture a positive opinion. 

 Schaefer, 15 the gifted physiologist of Edinburgh, has expressed 

 a supposition that new generation still occurs upon our earth 

 and escapes our observation because we do not know the con- 

 ditions which render such generation possible. This is an 

 interesting speculation, but with this possible exception we 

 must attribute to the saying, " omne vimim ex vivo" absolute 

 validity. 



With the progress of our knowledge we have made interest- 

 ing discoveries concerning the manner in which the uninter- 



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