Leonardo da Vinci But there is some enticing evidence that he may have practiced vegetarianism. Although he never mentions whether or not he personally ate meat, Leonardo's writings display a deep concern with animal welfare and horror over the fact that animals are raised to be killed and eaten by humans.
Isaac Newton was a vegetarian physicist and mathematician.
Socrates was a vegetarian Greek philsopher -Know thyself to be true. Socrates teachings had major influence on western philosophy. Both Plato and Aristotle were his disciples.