SEMI-CENTENNIAL CELEBRATION 131 



survey our morning meal, we consider in terms of chemistry 

 whether the repast is nutritively sufficient and what our chances 

 are in a physiological contest with its germs and germicides. 

 A glass of water on the railroad train is taken with proper scien- 

 tific reservations as to our future prospects in the hands of the 

 doctor and the nurse. The wisdom of the crucible and the 

 microscope have even been invoked in the domain of our 

 religious thought, sometimes to assure us concerning the verities 

 of the Christian religion and sometimes to assuage our fears as 

 to the certainties of divine retribution. 



But what is science and from whence comes its authority? 

 On what grounds may it rationally appeal to our confidence? 

 Those of us who accept its verdicts as a part of our intellectual 

 equipment, to whose activities truth is a blessing and error a 

 disaster, whose personal and material well-being may be jeopar- 

 dized by unsound conclusions, have a right to ask these questions 

 and ask them insistently. I crave your indulgence while I 

 attempt to answer them. 



Concise definitions of science are, "knowledge amassed, 

 severely tested, co-ordinated and systematized, specially regard- 

 ing those wide generalizations called the laws of nature." Or, 

 what is simpler, "knowledge gained and verified by exact obser- 

 vation and correct thinking.' ' The specifications, "knowledge 

 severely tested," and "knowledge gained and verified by exact 

 observation and correct thinking," clearly indicate, not only 

 what science is, but what it is not. It is not opinion, it is not 

 platform speculation, however eloquent, it is not truth diluted 

 or distorted by much repetition, it is not magazine exploitations 

 of the new and wonderful in a way that fires the imagination but 

 deceives the understanding, it is not theories partially supported 

 by data, it is not dangerous conclusions vitiated by confessed 

 errors or propped up on all sides by "ifs" and "provided," it is 

 not a "report of progress" that shows little more than what the 

 investigator hopes some time to prove and will take up again 



