PAGANISM AND NATIVE RELIGIONS

An ye harm none, do what ye will.
From the "Wiccan Rede."  The Wiccan Rede is a poem first published in Green Egg magazine in 1975, and now accepted by most Wiccans as authoritative.

For to whom is it not manifest that justice is increased through abstinence? For he who abstains from everything animated, though he may abstain from such animals as do not contribute to the benefit of society, will be much more careful not to injure those of his own species.
Porphyry, On Abstinence From Animal Food

"Can you really ask what reason Pythagoras had for abstaining from flesh? For my part I rather wonder both by what accident and in what state of soul or mind the first man did so, touched his mouth to gore and brought his lips to the flesh of a dead creature, he who set forth tables of dead, stale bodies and ventured to call food and nourishment the parts that had a little before bellowed and cried, moved and lived. How could his eyes endure the slaughter when throats were slit and hides flayed and limbs torn from limb? How could his nose endure the stench? How was it that the pollution did not turn away his taste, which made contact with the sores of others and sucked juices and serums from mortal wounds?"
Plutarch, On the Eating of Flesh

"This, 'abstain from the use of living creatures' [attributed to Pythagoras], exhorts to justice, with a due regard for what is of a kindred nature, and a sympathetic treatment of life which is similar to our own." 
Iamblichus, The Exhortation to Philosophy (Michigan: Phanes Press, 1988),  p. 111 (Thomas M. Johnson, translator).