PHYSIOLOGY 



use to anybody. 1 That is an extremist view. 

 Professor Karl Pearson, of University College, in 

 a recent address, has taken the opposite standpoint. 

 He says : " I am a scientific heretic. I do not 

 believe in Science for the sake of Science, but only 

 in its application to man. Thought and learning 

 are of little value unless they are translated into 

 action." Well, there you have the opposite poles 

 of opinion. The moderate person will take a 

 place somewhere between the two extremes. Let 

 me, however, introduce my argument concerning 

 the usefulness of what looks (or looked) like the 



1 I have let my allusion to a legendary professor stand as I actually 

 spoke it at the lecture. But since then my notice has been called to the 

 fact that it is no legend, and that it did not occur at the close of a busy 

 life. It was Professor Caley, of Cambridge, who made the remark. 

 He was a famous mathematician, and in speaking to his friends on a 

 piece of brilliant mathematical work he told them that " the most 

 delightful thing about it was that under no conceivable circumstances 

 would it be of the slightest use to anyone." In reference to this story 

 my friend Sir John MacAlister wrote me a letter from which I quote 

 the following sentences. They really point in a striking way the moral 

 I was trying to drive home. " I was dining last night with an old 

 friend and colleague of Professor Caley's, and reminded him of the story 

 you have quoted in your lecture. He assured me, as I always believed, 

 that it was * only his fun,' for no one had a firmer faith in the value of 

 all pure science, and his remark was only a sarcasm at the expense of the 

 so-called * practical ' scientists. The particular piece of work he was 

 referring to ultimately proved to be a remarkable example of the very 

 thing you are aiming at. The working out of the problem became 

 known as * Caley's Tree,' and proved to be the missing link in the efforts 

 of chemists to arrive at a solution of the arrangement of atoms, and 

 enabled them not only properly to order their discoveries, but success- 

 fully to prophesy new ones." 



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