DEATH AND RESURRECTION. 55 



of the extremely complicated mode of 

 propagation characteristic of insects, 

 doubts as to generatio spontanea increas- 

 ingly arose. It was, however, at a com- 

 paratively late time, or in the middle 

 of the seventeenth century, that Harvey 

 formulated his famous thesis, "omne 

 virum ex oro," or, as it has been later 

 said, "omne vivum e.v vivo" which we 

 may translate thus: "Life implies life; 

 all living beings descend from previous 

 existing parents " or negatively, "No liv- 

 ing being is generated from lifeless matter" 

 Thus, for the first time, the idea was 

 pronounced by natural science that life 

 is a specific force; an independent prin- 

 ciple, that has not its roots in the ma- 

 terial world. 



As generatio aequivoca leads to ma- 

 terialism, so Harvey's formula leads to 

 pure idealism. That these consequences 

 should have been seen from the begin- 

 ning, was so much the less to be ex- 

 pected since even today no such dis- 

 covery has been made or could have 

 been made, simply because no atten- 



