THE MEANING OF REGULARITIES 95 



nucleotide chains. It must select, by attracting or by rejecting, 

 those components that fit, out of the surplus of innumerable me- 

 tabolites being offered in the course of the life of the cell. The 

 screen, the sieve, the template: how many mechanomorphic con- 

 trivances could one not think of! I believe, however, that this is a 

 riddle that will not be solved through allegory. It is quite possible 

 that our biochemical thinking will have to acquire an entire new 

 dimension before we shall stop talking complete nonsense. But I 

 hope I shall not be accused of preaching metabiochemistry. 



There will be many among us who, having learned from the 

 often experienced defeat of easy or premature generalizations in 

 biochemistry, are allergic to attempts to bring order to the seem- 

 ing chaos of the living cell. They may rightly ask: Is there any 

 sense in looking for regularities in composition, such as I have 

 discussed before; to apply interior decoration to a continuum? 

 They are, of course, correct in protesting against the dictatorial 

 sway of half-baked hypotheses. But there will always be a time 

 in the natural sciences — and it will always be too early — when a 

 summary, a provisional and tentative summary, must be drawn 

 up. As long as we realize that the experimental sciences operate 

 under an unwritten statute of limitations, no harm will result. 



In the case of the nucleic acids it is particularly important to 

 ascertain whether any unifying principles governing their con- 

 struction can be discerned. They are considered by many people 

 to be the carriers of biological information. This rather ill-defined 

 notion views the DNA as the holder of the majority vote in the 

 transmission of hereditary properties and the RNA as the Execu- 

 tive Vice-President in charge of protein production. Be that as it 

 may — and there may be some surprises around the corner — bio- 

 logical information must be preserved; it must be transferred; 

 and, in the case of mutations, it must be changed. An incredible 

 amount of male handicraft is being wasted on information models. 

 But if there is any meaning to the concept of biological infor- 

 mation, the existence of regularities of the sort pointed out by me 

 before may furnish us the only chemical clue to systems through 

 which information is preserved or — and this is more important — 



References p. 98 



