The Least Harm Principle May Require that Humans Consume a Diet Containing Large Herbivores, Not a Vegan Diet


Based on his theory of animalrights, Regan concludes that humans are morallyobligated to consume a vegetarian or vegandiet. When it was pointed out to him that evena vegan diet results in the loss of manyanimals of the field, he said that while thatmay be true, we are still obligated to consumea vegetarian/vegan diet because in total itwould cause the least harm to animals (LeastHarm Principle, or LHP) as compared to currentagriculture. But is that conclusion valid? Isit possible that some other agriculturalproduction alternatives may result in leastharm to animals? An examination of thisquestion shows that the LHP may actually bebetter served using food production systemsthat include both plant-based agriculture and aforage-ruminant-based agriculture as comparedto a strict plant-based (vegan) system. Perhapswe are morally obligated to consume a dietcontaining both plants and ruminant(particularly cattle) animal products.

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Davis, S.L. The Least Harm Principle May Require that Humans Consume a Diet Containing Large Herbivores, Not a Vegan Diet. Journal of Agricultural and Environmental Ethics 16, 387–394 (2003).

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  • animal production
  • animal rights
  • least harm
  • moral vegetarianism
  • vegan