INTRODUCTORY 



having to conceal his ideas and not being able to 

 fight for them must have been horrible. A man 

 who discovered the marvellous movement of the 

 stars, and had to hide his emotion at the final 

 salvation of his work ! 



The ideas of Copernicus impelled Galileo to the 

 sacrifice of abjuration, and helped Bruno to the 

 honour of dying for them. 



Darwin, whose work raised a storm of protests 

 and keen polemics, had the immense satisfaction 

 of having his triumph during his lifetime. Pasteur 

 had a sharp and hot struggle, but his victory was 

 as rapid as it was complete. The struggle against 

 routine is terrible, because it has an organic origin 

 which is difficult to destroy ; and for the better 

 understanding of the mode of annihilating it the 

 following words of the eminent Eamon y Cajal on 

 this subject should be read : 



" If the suggestions of teachers and parents are 

 dictated by prejudices and false ideas about science, 

 religion, conduct, etc., they establish exclusive and 

 abnormal connections between certain groups of 

 cells, cerebrales, in the brain of the child, and the 

 psychological result will probably be a routine of 

 thought, a contempt of science, excessive credulity, 

 a longing for the marvellous, and other' vices of 

 thought as grave as they are difficult to uproot. 



"An education based on positive ideas, whole- 



