Michael Weisensee

“Humans — who enslave, castrate, experiment on, and fillet other animals — have had an understandable penchant for pretending animals do not feel pain. A sharp distinction between humans and 'animals' is essential if we are to bend them to our will, make them work for us, wear them, eat them — without any disquieting tinges of guilt or regret. It is unseemly of us, who often behave so unfeelingly toward other animals, to contend that only humans can suffer. The behavior of other animals renders such pretensions specious. They are just too much like us.”
― Carl Sagan

“One farmer says to me, 'You cannot live on vegetable food solely, for it furnishes nothing to make bones with;' and so he religiously devotes a part of his day to supplying his system with the raw material of bones; walking all the while he talks behind his oxen, which, with vegetable-made bones, jerk him and his lumbering plow along in spite of every obstacle.”
― Henry David Thoreau, Walden or, Life in the Woods

“A human body in no way resembles those that were born for ravenousness; it hath no hawk’s bill, no sharp talon, no roughness of teeth, no such strength of stomach or heat of digestion, as can be sufficient to convert or alter such heavy and fleshy fare. But if you will contend that you were born to an inclination to such food as you have now a mind to eat, do you then yourself kill what you would eat. But do it yourself, without the help of a chopping-knife, mallet or axe, as wolves, bears, and lions do, who kill and eat at once. Rend an ox with thy teeth, worry a hog with thy mouth, tear a lamb or a hare in pieces, and fall on and eat it alive as they do. But if thou had rather stay until what thou eat is to become dead, and if thou art loath to force a soul out of its body, why then dost thou against nature eat an animate thing? There is nobody that is willing to eat even a lifeless and a dead thing even as it is; so they boil it, and roast it, and alter it by fire and medicines, as it were, changing and quenching the slaughtered gore with thousands of sweet sauces, that the palate being thereby deceived may admit of such uncouth fare.”
― Plutarch

“People often say that humans have always eaten animals, as if this is a justification for continuing the practice. According to this logic, we should not try to prevent people from murdering other people, since this has also been done since the earliest of times.”
― Isaac Bashevis Singer