THE FOOD QUESTION 



but regard those whose steps logically 

 lead them to conscious potatoes and 

 cabbage heads as well on the way to 

 absurdity. 



Quite another aspect of this problem in 

 cell life, and one which apparently affords 

 considerable support to the anti-vitalists, 

 is presented by some researches in medical 

 science, on the subject of Immunity. To 

 determine why a single attack of some 

 infectious diseases renders that person im- 

 mune against a second attack of the same, 

 or why some persons seem to have a nat- 

 ural immunity against infections in gen- 

 eral, while others are very susceptible to 

 them, or why some infections confer only 

 temporary immunity or none at all against 

 their recurrence, are certainly questions 

 of much practical importance. Their in- 

 vestigation has led recently to some of the 

 most abstruse speculations in the history 

 of medicine. Now theories are valuable 

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