10 THE CONTROL OF LIFE 



health ; the foundations of agriculture and medicine, 

 for instance, are pre-historic ; and there is no clear 

 line to be drawn between the empirical and the scientific 

 stage. But what is distinctively modern is the idea of 

 an all-round utilisation of Science as a basis for action, 

 the determined attempt to substitute the rational for 

 the empirical, the growing habit of focusing scientific 

 inquiry on practical puzzles, the recognition of scientific 

 investigation as an agency likely to produce well-being 

 as well as enlightenment. Our present thesis is, that 

 Science can do far more for human life than it has 

 hitherto been allowed to do or asked to do. 



In illustrating this thesis we do not take any narrow 

 view of Science. For we mean by Science — all sys- 

 tematised, verifiable, and communicable knowledge, 

 reached by reflection on the impersonal data of observa- 

 tion and experiment. Science is precise, co-ordinated 

 knowledge about all of reality that can be studied by 

 recognised methods of measurement, registration, and 

 experiment. One of the best definitions is that given 

 by Dr. Trotter in his Instincts of the Herd — " a body 

 of knowledge derived from experience of its material, 

 and co-ordinated so that it shall be useful in fore- 

 casting and, if possible, directing the future behaviour 

 of that material." 



But only omniscience could draw a circle including 

 all scientific knowledge and excluding all else. Dif- 

 ferent orders of facts are unequally amenable to 

 measurement, experiment, and other scientific methods. 

 For this reason, and for historical reasons, the Sciences 



