PREFACE TO THE FIRST EDITION. XXi 



been gained by the author of this " Ignorabimus," the most 

 deserving student of the electricity of nerves and muscles, 

 we must here most emphatically protest in the name of 

 advancing natural knowledge and of all science capable 

 of development. Had our one-celled Amoeba-ancestors of 

 the Laurentian Period been told that their descendants 

 would afterwards, in the Cambrian Period, produce a many- 

 celled Worm-like organism possessed of skin and intestine, 

 muscles and nerves, kidneys and blood-vessels, they would 

 certainly not have believed ; nor, again, would these Worms 

 have believed, had they been told that their descendants 

 would develop into skull-less Vertebrates, such as the 

 Amphioxus ; nor would these Skull-less Animals have 

 credited that their posterity would ever become Skulled 

 Animals (Craniota). Our Silurian Primitive-fish ancestors 

 would have been equally hard to convince that their off- 

 spring of the Devonian Period would acquire amphibian 

 form, and yet later, in the Triassic Period, would appear 

 as Mammals ; the latter, again, would have deemed it im- 

 possible that, in Tertiary times, a very late descendant 

 of theirs would acquire human form, and would gather the 

 splendid fruits of the tree of knowledge. All these would 

 have answered : " We shall never change, nor shall we 

 ever understand the history of our evolution! Nunquam 

 mutabimur ! Semper ignordbimus ! " 



With this Ignorabimus the Berlin school of Biology 

 tries to stop science in its advance along the paths of 

 evolution. This seemingly humble but really audacious 

 "Ignorabimus" is the " Ignoratis" of the infallible 

 Vatican and of the " black international " which it leads ; 

 that mischievous host, against which the modern civilized 



