In 1883, Jean Paul Richter published The Literary Works of Leonardo da Vinci. In the two volumes of this fundamental work on Leonardo’s research, Richter arranged collected notes and added valuable comments. Although the scientific community has known of Leonardo’s vegetarianism since then, this subject has not been further investigated. To explore the significance of Leonardo’s vegetarianism, my work starts out with a rough sketch of the history of cruelty-free nutrition in chapter 1. In chapter 2, I discuss fallacies surrounding this subject, and in chapter 3, I search for possible inspirations behind Leonardo’s vegetarianism. I have collected relevant citations of Leonardo on animals and nutrition and arranged them chronologically to map his inner maturation process in chapter 4. (25 further citations are provided in appendix 5). In chapter 5, I investigate which factors may have promoted Leonardo’s change in perspective with regard to animal ethics. Finally, chapter 6 deals with the significance of the subject in Leonardo’s thought.
Keywords: Leonardo da Vinci, vegetarianism, cruelty-free nutrition, history of vegetarianism, vegetarian philosophers