32 APHORISMS AND REFLECTIONS 



It is a great many years since, at the outset of my 

 career, I had to think seriously what life had to offer 

 that was worth having. I came to the conclusion 

 that the chief good, for me, was freedom to learn, 

 think, and say what I pleased, when I pleased. I 

 have acted on that conviction, and have availed 

 myself of the " rara tempprum felicitas ubi sentire 

 quae velis, et quae sentias dicere licet," which is now 

 enjoyable, to the best of my ability ; and though 

 strongly, and perhaps wisely, warned that I should 

 probably come to grief, I am entirely satisfied with 

 the results of the line of action I have adopted. 



The scientific imagination always restrains itself 

 within the limits of probability. 



It is a "law of nature," verifiable by everyday 

 experience, that our already formed convictions, our 

 strong desires, our intent occupation with particular 

 ideas, modify our mental operations to a most mar- 

 vellous extent, and produce enduring changes in the 

 direction and in the intensity of our intellectual and 

 moral activities. 



Men can intoxicate themselves with ideas as 

 effectually as with alcohol or with bang, and produce, 

 by dint of intense thinking, mental conditions hardly 

 distinguishable from monomania. 



