DESIGN FOR A BRAIN 18/7 



regulation thus permits the possibility of amplifying the amount 

 of regulation; hence its importance. 



18/7. Living organisms came across this possibility aeons ago, 

 for the gene-pattern is a channel of communication from parent 

 to offspring: 4 Grow a pair of eyes,' it says, ' they'll probably 

 come in useful; and better put haemoglobin into your veins — 

 carbon monoxide is rare and oxygen common.' As a channel of 

 communication it has a definite, finite capacity, Q say. If this 

 capacity is used directly, then, by the law of requisite variety, 

 the amount of regulation that the organism can use as defence 

 against the environment cannot exceed Q. To this limit, the 

 non-learning organisms must conform. If, however, the regula- 

 tion is done indirectly, then the quantity Q, used appropriately, 

 may enable the organism to achieve, against its environment, an 

 amount of regulation much greater than Q. Thus the learning 

 organisms are no longer restricted by the limit. 



The possibility of such ' amplification ' is well known in other 

 ways. If a child wanted to discover the meanings of English 

 words, and his father had only ten minutes available for instruc- 

 tion, the father would have two possible modes of action. One is 

 to use the ten minutes in telling the child the meanings of as many 

 words as can be described in that time. Clearly there is a limit to 

 the number of words that can be so explained. This is the direct 

 method. The indirect method is for the father to spend the ten 

 minutes showing the child how to use a dictionary. At the end 

 of the ten minutes the child is, in one sense, no better off ; for not 

 a single word has been added to his vocabulary. Nevertheless 

 the second method has a fundamental advantage ; for in the future 

 the number of words that the child can understand is no longer 

 bounded by the limit imposed by the ten minutes. The reason 

 is that if the information about meanings has to come through 

 the father directly, it is limited to ten-minutes' worth; in the 

 indirect method the information comes partly through the father 

 and partly through another channel (the dictionary) that the 

 father's ten-minute act has made available. 



In the same way the gene-pattern, when it determines the growth 

 of a learning animal, expends part of its resources in forming a 

 brain that is adapted not only by details in the gene-pattern but 

 also by details in the environment. The environment acts as the 



236 



