XU PREFACE 



science in his daily work. The fact that the first six chapters 

 are largely devoted to drawing distinctions of this kind may 

 make the book start too slowly for some readers. Such peo- 

 ple might better plunge right in at Chapter 7, "How to 

 Become a Scientist." 



Nevertheless, I can't help hoping that a considerable 

 number of readers will find it interesting to review some of 

 the thinking that has been done over the years on the nature 

 of knowledge. Only in this way can one really understand 

 what it is that gives science its peculiar power and its almost 

 equally surprising limitations. I am well aware that many, 

 perhaps most, competent scientists care httle about the 

 philosophy of science, but I found it impossible to write a 

 book about being a scientist without first trying to say a 

 little bit about what science is. 



The last three chapters are perhaps the most personal 

 in the book and they deal with subjects which are viewed 

 very differently by different people. The observations and 

 opinions put forward here represent a very tentative and 

 preliminary attempt to describe some of the relationships 

 between science and other essential forms of human activity. 



I suspect that at least the last chapter, "Science and Pol- 

 icy," will seem very remote to young people attempting to 

 choose a career. I included it for at least four reasons. ( 1 ) 

 It is important for everyone to recognize that science is in- 

 volved intimately and continuously with decision-making of 

 the greatest importance for our daily Uves. (2) Anyone go- 

 ing into science may be involved in high policy discussions 

 much sooner than he might suppose. ( 3 ) We are still in the 

 process of working out a satisfactory relationship between 

 science and the world of affairs, and it seems desirable to 

 stimulate as many people as possible to start thinking about 

 it as soon as possible. (4) The writing of this chapter gave 

 me an opportunity to clarify my own thinking. 



