10/6 AN INTRODUCTION TO CYBERNETICS 



which to buy. I test each for a day against similar disturbances 

 and then look at the records of the temperatures; they are as in 

 Fig. 10/6/1: 



Tltiie 





Fig. 10/6/1 



There is no doubt that Model B is the better; and I decide this pre- 

 cisely because its record gives me no information, as does A's, about 

 what disturbances, of heat or cold, came to it. The thermometer 

 and water in bath B have been unable, as it were, to see anything of 

 the disturbances D. 



The same argument will apply, with obvious modifications, to the 

 automatic pilot. If it is a good regulator the passengers will have 

 a smooth flight whatever the gustiness outside. They will, in short, 

 be prevented from knowing whether or not it is gusty outside. Thus 

 a good pilot acts as a barrier against the transmission of that 

 information. 



The same argument applies to an air-condition©r. If I live in an 

 air-conditioned room, and can tell, by the hotness of the room, 

 that it is getting hot outside, then that conditioner is failing as a 

 regulator. If it is really good, and the blinds are drawn, I shall 

 be unable to form any idea of what the outside weather is like. The 

 good conditioner blocks the flow inwards of information about the 

 weather. 



The same thesis applies to the higher regulations achieved by such 

 activities as hunting for food, and earning one's daily bread. Thus 

 while the unskilled hunter or earner, in difficult times, will starve 

 and will force his liver and tissues (the essential variables) to extreme 

 and perhaps unphysiological states, the skilled hunter or earner 

 will go through the same difficult times with his liver and tissues 

 never taken to extremes. In other words, his skill as a regulator 

 is shown by the fact, among others, that it prevents information 



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