SCIENTIFIC METHOD 79 



In the more exact sciences such as astronomy 

 the verification of the uniformity is complete, 

 since the routine of sequences can be summed 

 up in rigid mechanical formulae. We cannot 

 do this in Biology, yet here also we make and 

 verify the postulate of the Uniformity of Nature. 

 In spite of a strong personal element in many 

 living creatures which makes their behaviour in 

 complicated situations unpredictable, there are 

 uniformities both of action and reaction. With- 

 out these, indeed, there could not be a science 

 of Biology at all, but with these there is a basis 

 for calculation, prediction, and action, which is 

 reliable, though not to the same degree as that 

 afforded by the more exact sciences. 



SUMMARY. The logic of scientific discovery is 

 chiefly an intricate interlacing of induction and 

 deduction. While genius has counted for much in 

 the history of science, many great discoveries have 

 been the harvest of a keen eye and an inquisitive 

 spirit. The first step in scientific procedure is to 

 collect data, and all science begins with measure- 

 ment. The second step is the arrangement and 

 classification of facts. Auxiliary to this and to 

 formulation is the process of analysis or reduction 

 to simpler terms. In order to fulfil the aim of 

 describing facts of experience as exactly as possible, 

 as simply as possible, as completely as possible, 

 it is often necessary to try one hypothesis after 



