Quote by Ralph Waldo Emerson
The value of a principle is the number of things it will explain; and there is no good theory of disease which does not at once suggest a cure.
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Summary
This quote emphasizes the importance of principles or theories that have practical applications. It suggests that the true value of a principle lies in its ability to explain a wide range of phenomena or situations. Furthermore, it suggests that a good theory or principle should not only provide an explanation but also point towards possible solutions or cures. In the context of disease, this means that a valid theory should not only help us understand the causes and nature of a disease but also provide insights into potential treatments or remedies.