EXPERIMENTS WITH LIVING HUMAN BEINGS. 753 



unexpected infusoria that are killed by quinine, and announces to the 

 world in one breath a theory of the disease and a specific for its cure, 

 without apparently suspecting, what is now known, that the presence of 

 infusoria might be a coincidence or effect and not a cause. 



To all this it may be said that practically we do find out the true 

 value of medicines and their objective action on the human body with-- 

 out systematically eliminating any of the six elements of error here 

 pointed out. This is to be allowed ; but the admission of the fact re- 

 quires also an explanation of the way in which these errors are in prac- 

 tice actually eliminated, although unintentionally and unsystematically, 

 and I may say also, most unscientificalh'. 



It is by an immense number of experiments or trials on a large vari- 

 ety of cases, at different times, by different observers, and under vary- 

 ing conditions, that medical science has been able, after centuries of 

 doubt and struggle, to arrive at some few real scientific facts in regard 

 to the action of medicines. If these six elements of error had, from the 

 first, been everywhere recognized and comprehended and systematically 

 guarded against, the process of finding the truth in this department 

 might have been abridged by hundreds of years. The method by which, 

 in practice, physicians learn the action of any new remedy, is to give it 

 to a number of cases, and then to watch and report the results ; another 

 physician repeats the experiments on a difi"erent set of cases ; he also 

 notes the results : and this process goes on perhaps for years, until in 

 lapse of time the profession, without being able to give precise and con- 

 vincing reasons for their faith, slowly and instinctively settles down to 

 the persuasion that the effects claimed for the remedy are genuine, and 

 act accordingly. 



In many instances they are right in this conclusion ; but how awk- 

 wardly and in what a roundabout way, and through what useless and 

 wearying toil, have they, in dou*bt and distrust and suspicion, finally 

 reached that goal ! All the trials with the remedy, from beginning to 

 end, have been impaired in scientific value by some one or all of the six 

 elements of error ; but through the immensity and variety of the experi- 

 ments, extending through a long period, these errors have been uncon- 

 sciously and unwittingly eliminated, so that only the solid fact is left. 

 Tliis unconscious elimination or rather leaving behind of errors, after 

 the analogy of the formation of the universe according to tlie nebular 

 hypothesis, takes place in this manner : In the first hundred cases 

 treated there will be perhaps one of two, or more, who have no faith in 

 and no expectation from it, good or bad ; these few obtain the real ob- 

 jective effects of the remedy, while all the others deceive, more or less, 

 themselves and their physician. In subsequent experiments by other 

 observers, some of whom perhaps are less hopeful than the original inves- 

 tigator, the same unconscious and irregular elimination takes place, until 

 the objective power of the remedy may for all practical needs be regard- 

 ed as established. Such is the history and philosophy of medical experi- 



