Epidemics that formerly wiped out from 15 to 50 per cent of a population 

 have come under control. Several communicable diseases are no longer the 

 leading causes of death. Not only are people generally better nourished and 

 better able to work and play, but the life span has been substantially length- 

 ened. We have not conquered death, but we have postponed the funerals 

 for millions of men, women and children now living, by an average of ten 

 years or more. 



The many measurable improvements in health and the tremendous in- 

 crease in usable materials of plant and animal origin are due to advances in 

 various branches of biology. But biology does not advance by itself. Basic 

 reasons why all sciences developed rapidly in the past century are the great ex- 

 pansion in popular education, a great increase in the amount of reading, and 

 improved communications among workers of different nations. But these 

 things are not independent happenings. They are related to one another, and 

 they are related to the so-called industrial revolution, which made possible 

 the rapid development of productive technology. These industrial changes 

 set free more and more time that people could use for exploring, ex- 

 perimenting, thinking and research. The resulting gains in turn helped to 

 accelerate the process. 



These tremendous gains have not been universal. Large sections of the 

 population are still undernourished, badly housed, suffering from preventable 

 sicknesses and deficiencies, and still living in gross ignorance and superstitions 

 and fear. Yet there is hardly a farmer who does not make use of modern 

 science. He uses chemical knowledge about fertilizers, bacteriological knowl- 

 edge about life within the soil, soil knowledge and water knowledge about 

 plowing and cultivating. He uses genetic knowledge in deciding what types 

 of seed to use, mycological knowledge and entomological knowledge in pro- 

 tecting the crops against pests. His daily work with his livestock involves a 

 wide range of specialist knowledge regarding each particular type of animal, 

 and again he uses the knowledge of the biochemist, the bacteriologist, the 

 geneticist, the physiologist. 



It would be absurd to pretend that each farmer is an expert in all branches 

 of biology, as well as the other sciences. Yet his present-day performances 

 and his achievements would not be possible without the work of hundreds of 

 specialists. Indeed, if he could himself carry in his own head all the knowledge 

 of these many specialists, he could not possibly use that knowledge through his 

 own activities. That is to say, this modern farmer makes daily use of countless 

 discoveries from laboratories scattered throughout the world; he spreads 

 seeds, fertilizers, poisons and sprays assembled from all quarters of the earth; 

 and he works the soil with machinery brought from widely scattered factories 

 and made of many different metals and other materials which he could not 

 gather by himself in a lifetime. 



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