12 - The Cell 



upon superstition to cover his ignorance of 

 natural events; and this led to the creation 

 of many gods: of the wind, the sun, the 

 harvest, and so forth. But even at the dawn 

 of civilization, some capacity for accurate 

 observation was gradually developing, as can 

 be seen in the records of animal and plant 

 life that the cave dwellers painted by torch- 

 light on the walls of their ancient homes 

 (Fig. 1-7). 



during the past 75 years — well within the 

 memory of our fathers and grandfathers — 

 research laboratories have developed in every 

 important university, in every industry, and 

 in every part of the world. This new group of 

 workers has been carefully trained in the 

 scientific method, and has widely extended 

 the frontiers of natural science. Consequently 

 the present-day student of biology, chemistry, 

 physics, or other science begins work with a 



Fig. 1-7. Scientific observation began in prehistoric times. Cro-Magnon artists in the Cavern 

 of Font de Gaume. (Courtesy of the American Museum of Natural History, New York.) 



Early civili/ed men, especially the Egyp- 

 tians, Creeks, and Romans, began to use 

 direct observation rather than superstitious 

 tradition as the basis of their thinking. In fact 

 the ancients began to test their conclusions 

 by experiment, and many roots of otir scien- 

 tific knowledge can be traced back into the 

 classical period. 



But the scientific attitude did not survive. 

 After the decline of the Romans, supersti- 

 tion prevailed again for almost fourteen cen- 

 turies. The scant scientific knowledge that 

 survived the Dark Ages was "second hand" 

 — passed on from generation to generation, 

 chiefly by the medieval monks. 



During the Renaissance, much of the an- 

 cient learning was revived, and science began 

 to gain a new momentum. Gradually the sci- 

 entific method came into its own. Especiallv 



double heritage. He receives not only a large 

 fund of knowledge, tested by the scientists of 

 every nation, but also a most useful tool — the 

 fully developed method of science. 



The Scientific Method. Unquestionably, 

 trial-and-error procedures play an important 

 part in all research, especially in the earlv 

 exploratory stages. Behind these probings. 

 however, there usually stands a well-defined 

 plan, in which the reasoning is partly induc- 

 tive and partly deductive. The scientific 

 method involves four steps — and the same 

 steps are taken over and over again, as new 

 ground is being gained and tested. 



1. Observation. The primary basis of all 

 scientific thinking is observation — preciselv 

 quantitative and, above all, unbiased bv any 

 preconception as to the significance of the 

 observed data. Nowadays especiallv, the ob- 



