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Every man takes the limits of his own field of vision for the limits of the world.
—Arthur Schopenhauer
Physicians deal with individuals and try to explain the phenomena that they observe in their world in terms that make sense to them. Rajput summarizes the approach to the cause of Parkinson's disease with all encompassing conciseness when he argues that the causes are "genetic, environmental, and environmental trigger in genetically predisposed individuals." He goes on to marshall evidence from epidemiologic, twin, and toxin studies, some of it his original work, supporting an environmental cause. Within the limits of his paradigm he is persuasive.
Riggs, a neurologist with an unusual gift for mathematics and global analyses, argues with similar persuasiveness that the rise in Parkinson's disease mortality can be explained by interdisease competition, without the need to invoke environmental worsening.
Both Rajput and Riggs may be partially right since both interdisease