“ The reason the beasts give among themselves is that Man is the weakest and most defenseless of all living things, and it is unsportsmanlike to touch him. They say too—and it is true—that man-eaters become mangy, and lose their teeth. ”
 Rudyard Kipling, The Jungle Book (1894). copy citation

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“The real reason for this is that man-killing means, sooner or later, the arrival of white men on elephants, with guns, and hundreds of brown men with gongs and rockets and torches. Then everybody in the jungle suffers. The reason the beasts give among themselves is that Man is the weakest and most defenseless of all living things, and it is unsportsmanlike to touch him. They say too—and it is true—that man-eaters become mangy, and lose their teeth. The purr grew louder, and ended in the full-throated “ Aaarh! ” of the tiger’s charge.
Then there was a howl—an untigerish howl—from Shere Khan. “ He has missed, ” said Mother Wolf. “ What is it? ”
“ The fool has had no more sense than to jump at a woodcutter’s campfire, and has burned his feet, ” said Father Wolf with a grunt.” source