INTRODUCTION 5 



4. Have sufficient light to make the subject stand 

 forth so as to be seen clearly. This implies a proper 

 background — a background built up in the study of 

 science by ascertaining what has gone before, and what 

 causes have produced the particular historical soil upon 

 which the seed of men's ideas have been able to grow. 

 In other words, we wish to have all the facts that can be 

 found, so as to throw the subject under consideration 

 into the full glare of day. Shadows should be excluded 

 as much as possible. 



5. See that the subject is in focus, which means that in 

 any given case, it must stand forth in bold relief. It must 

 not fade away in the distance and become blurred by 

 prejudices or desires. No vagaries of thought must be 

 permitted. Our reasoning must be clear and definite. Our 

 whole system must be built up philosophically and 

 logically. 



6. Decide upon how large an opening we are to allow 

 our lens; that is, within what narrow limits we are to 

 discuss the subject under consideration. 



7. Decide upon the length of time for the exposure, 

 which, in a scientific treatise, means that we must know 

 that sufficient time has elapsed to make our experiment 

 valid and positive. 



8. If we read of the results of others, take into con- 

 sideration the temperamental make-up of the individual 

 writing as well as of ourselves and other readers who later 

 are to pass judgment thereon. 



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