GENERAL DEVELOPMENT OF A LOCALIZATION PROGRAM 533 



tions, using tracer and chromatographic techniques, so that the demonstra- 

 tion of an in vivo block at the sites indicated can be made. The primary 

 sites of action of even some of the longest known and most commonly 

 used enzyme inhibitors when acting on living tissue are uncertain because 

 adequate analysis of their actions has never been made. 



It is believed that the planning of a rather rigorous program for local- 

 ization is advisable but in all problems involving metabolism or living ma- 

 terial there frequently arise unforeseen difficulties that block the way to 

 the final solution. At the present time, in any event, a foolproof key for the 

 localization of an inhibitor's action cannot be presented; if this were pos- 

 sible, the problem would lose some of its interest because we would be de- 

 prived of the excitement of probing into unknown and complex systems. 

 Indeed, if the situation were as simple as all that, technicians could be relied 

 upon to undertake and solve such problems. Therefore, a final word should 

 be said for those all-important abilities of a scientist, abilities that transcend 

 all keys or formalized systems — the ability to choose the right experiments 

 and the ability to observe accurately and with insight. These abilities might 

 be attributed in part to intuition, which is perhaps the inner and uncon- 

 scious organization of knowledge and experience in a field, and is allied to 

 the ability of some physicians to diagnose correctly from the same infor- 

 mation that leaves others puzzled, often by mental processes that they 

 themselves cannot explain. The ability to observe extends not only to the 

 actual experiments but to data and the representations of data. In the 

 course of the localization of an inhibition site, it is quite likely that unexpect- 

 ed results will appear at times. These must be recognized and put on an 

 equal status with the data for which the studies were made. It is frequently 

 the accidental observation that eventually leads to the solution. The an- 

 swer mav not lie in what one seeks but in what one finds. 



