THE ART OF SCIENTIFIC INVESTIGATION 



devoted to it. It is as well to remember this when criticising 

 someone's suggestion, because you may offend and discourage 

 him if you scorn the idea. A corollary to this observation that 

 an hypothesis is a very personal matter, is that a scientist usually 

 works much better when pursuing his own than that of someone 

 else. It is the originator who gets both the personal satisfaction 

 and most of the credit if his idea is proved correct, even if he 

 does not do the work himself A man working on an hypothesis 

 which is not his own often abandons it after one or two 

 unsuccessful attempts because he lacks the strong desire to con- 

 firm it which is necessary to drive him to give it a thorough trial 

 and think out all possible ways of varying the conditions of 

 the experiment. Knowing this, the tactful director of research 

 tries to lead the worker himself to suggest the line of work 

 and then lets him feel the idea was his. 



Precautions in the use of hypothesis 



(a) Not to cling to ideas proved useless. Hypothesis is a tool 

 which can cause trouble if not used properly. We must be 

 ready to abandon or modify our hypothesis as soon as it is shown 

 to be inconsistent with the facts. This is not as easy as it sounds. 

 When delighted by the way one's beautiful brain-child seems to 

 explain several otherwise incongruous facts and offers promise 

 of further advances, it is tempting to overlook an observation 

 that does not fit into the pattern woven, or to try to explain 

 it away. It is not at all rare for investigators to adhere to their 

 broken hypotheses, turning a blind eye to contrary evidence, 

 and not altogether unknown for them deliberately to suppress 

 contrary results. If the experimental results or observations are 

 definitely opposed to the hypothesis or if they necessitate unduly 

 complicated or improbable subsidiary hypotheses to accom- 

 modate them, one has to discard the idea with as few regrets 

 as possible. It is easier to drop the old hypothesis if one can 

 find a new one to replace it. The feeling of disappointment too 

 will then vanish. 



It was characteristic of both Darwin and Bernard that they 

 were ready to drop or modify their hypotheses as soon as they 

 ceased to be supported by the facts observed. The scientist who 

 has a fertile mind and is rich in ideas does not find it so difficult 



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