50 THE PATH OF SCIENCE 



to put those facts in what we may term a "suspense account," 

 reserving judgment of their validity until a consensus by 

 qualified observers is reached. In the history of science, 

 many observations have been published that were not ac- 

 cepted immediately as accurate. Some of them were later 

 agreed to be erroneous; many were confirmed by further 

 study. 



A requirement for this agreement between different ob- 

 servers is that they be critical of the method of observation 

 employed. It is well known to psychologists, for instance, 

 that the reports of different observers of a series of incidents 

 may disagiee. George quotes an experiment by A. AV. P. 

 Wolters * in which a disorderly incident was deliberately 

 introduced into the middle of a lecture he was giving on 

 observation. The students ^\ ere then asked to write at once 

 a detailed account of what had occurred. An accurate and 

 full report would have contained ten essential points of de- 

 tail. The average number of points correctly reported was 

 3,5, and the reports contained many completely false state- 

 ments, it being impossible for some of the details to have 

 occurred in that particular room. The cause of these dis- 

 crepancies is, of course, the unanticipated nature of the 

 events. Reliable observations can be obtained only if the 

 observer is paying attention to the action observed. The 

 more suddenly the phenomenon happens and the more un- 

 expected it is, the less likely are reliable observations to be 

 made. 



A second factor in observation is that the observer will see 

 more if he is not only looking at what is to be observed, but 

 looking for it. A histological section under a microscope 

 will convey no information to one who is ignorant of minute 

 anatomy. I recall once studying an x-ray photograph on an 

 illuminator. The photograph had been taken as a test of the 

 photographic plate. Some one looking over my shoulder 

 said: "Isn't that a beautiful photograph?" To this I replied 



* George, op. cit., p. 79. 



