The sick are the greatest danger for the healthy; it is not from the strongest that harm comes to the strong, but from the weakest.
 Friedrich Nietzsche, On the Genealogy of Morality (1887). copy citation

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Author Friedrich Nietzsche
Source On the Genealogy of Morality
Topic danger harm
Date 1887
Language English
Reference
Note Translated by Horace B. Samuel
Weblink https://en.wikisource.org/wiki/The_Genealogy_of_Morals

Context

“The more normal is this sickliness in man—and we cannot dispute this normality—the higher honour should be paid to the rare cases of psychical and physical powerfulness, the windfalls of humanity, and the more strictly should the sound be guarded from that worst of air, the air of the sick-room. Is that done? The sick are the greatest danger for the healthy; it is not from the strongest that harm comes to the strong, but from the weakest. Is that known? Broadly considered, it is not for a minute the fear of man, whose diminution should be wished for; for this fear forces the strong to be strong, to be at times terrible—it preserves in its integrity the sound type of man.” source