The question of whether there are any ethical duties toward animals was hotly debated, and the arguments in dispute were quite similar to the ones familiar in modern discussions on animal rights. Vegetarianism was usually part and parcel of religious convictions connected with the concept of transmigration of the soul (metempsychosis). There was a widely held belief, popular among both vegetarians and non-vegetarians, that in the Golden Age of the beginning of humanity mankind was strictly non-violent. In that utopian state of the world hunting, livestock breeding, and meat-eating, as well as agriculture were unknown and unnecessary, as the earth spontaneously produced in abundance all the food its inhabitants needed. This myth is recorded by Hesiod ("Works and Days" 109sqq.), Plato ("Statesman" 271–2), the famous Roman poet Ovid ("Metamorphoses" 1,89sqq.), and others. Ovid also praised the Pythagorean ideal of universal nonviolence ("Metamorphoses" 15,72sqq.).