"[I]t is my view that a vegetarian manner of living by its purely physical effect on the human temperament would most beneficially influence the lot of mankind."

Albert Einstein, letter to Hermann Huth, December 27, 1930 (Archival Call Number 46-756)

"A man can live and be healthy without killing animals for food; therefore, if he eats meat, he participates in taking animal life merely for the sake of his appetite. And to act so is immoral."

Leo Tolstoy, letter to Dr. Eugen Heinrich Schmitt

"[I]f one person is unkind to an animal it is considered to be cruelty, but where a lot of people are unkind to a lot of animals, especially in the name of commerce, the cruelty is condoned and, once large sums of money are at stake, will be defended to the last by otherwise intelligent people."

Ruth Harrison, Animal Machines

"The day will come when the idea that, to feed themselves, men of the past raised and massacred living beings and complacently exposed their tattered flesh in shop windows, will no doubt inspire the same revulsion as that of travelers in the 16th or 17th centuries witnessing the cannibal meals of the American, Oceanian or African savages."

Claude Lévi-Strauss, The wise lesson of mad cows (article in Études rurales, 157-158 | 2001)

"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 who 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? ... It is certainly not lions and wolves that we eat out of self-defense; on the contrary, we ignore these and slaughter harmless, tame creatures without stings or teeth to harm us, creatures that, I swear, Nature appears to have produced for the sake of their beauty and grace. ... But nothing abashed us, not the flower-like tinting of the flesh, not the persuasiveness of the harmonious voice, not the cleanliness of their habits or the unusual intelligence that may be found in the poor wretches. No, for the sake of a little flesh we deprive them of sun, of light, of the duration of life to which they are entitled by birth and being."

Plutarch, Moralia (Volume XII)

"O mortals, do not pollute your bodies with a food so impious! You have the fruits of the earth, you have apples, bending down the branches with their weight, and grapes swelling to ripeness on the vines; you have also delicious herbs and vegetables which can be mellowed and softened by the help of fire. Nor are you without milk or honey, fragrant with the bloom of thyme. The earth, prodigal of her wealth, supplies you her kindly sustenance and offers you food without bloodshed and slaughter."

Attributed to Pythagoras by Ovid, Metamorphoses (Book XV, lines 75-82)

"Bernard Shaw says that as long as men torture and slay animals and eat their flesh, we shall have war . . . While we are ourselves the living graves of murdered animals, how can we expect any ideal conditions on the earth?"

Isadora Duncan, My Life (the quote is often misattributed to Shaw himself)

"I believe I am not interested to know whether Vivisection produces results that are profitable to the human race or doesn't. To know that the results are profitable to the race would not remove my hostility to it. The pains which it inflicts upon unconsenting animals is the basis of my enmity towards it, and it is to me sufficient justification of the enmity without looking further."

Mark Twain, The Pains of Lowly Life (originally written as a letter to the London Anti-Vivisection Society, May 26, 1899)

"To a man whose mind is free there is something even more intolerable in the sufferings of animals than in the sufferings of men. For with the latter it is at least admitted that suffering is evil and that the man who causes it is a criminal. But thousands of animals are uselessly butchered every day without a shadow of remorse. If any man were to refer to it, he would be thought ridiculous.—And that is the unpardonable crime. That alone is the justification of all that men may suffer. It cries vengeance upon all the human race."

Romain Rolland, Jean-Christophe Journey's End

"I have no doubt that it is a part of the destiny of the human race, in its gradual improvement, to leave off eating animals, as surely as the savage tribes have left off eating each other when they came in contact with the more civilized."

Henry David Thoreau, Walden (Chapter XI, Higher Laws)

"We humans torture and kill two billion sentient living beings every week. Ten thousand entire species are wiped out every year because of the actions of one species, and we are now facing the sixth mass extinction in cosmological history. If any other organism did this, a biologist would call it a virus."

Philip Wollen, Ethics in a Meat-Free World speech at TEDxMelbourne, August 24, 2012

"What do they know—all those scholars, all those philosophers, all the leaders of the world[...]? They have convinced themselves that man, the worst transgressor of all the species, is the crown of creation. All other creatures were created merely to provide him with food, pelts, to be tormented, exterminated. In relation to them, all people are Nazis; for the animals, it is an eternal Treblinka."

Isaac Bashevis Singer, The Letter Writer

"Imagine that you are creating a fabric of human destiny with the object of making men happy in the end, giving them peace and rest at last, but that it was essential and inevitable to torture to death only one tiny creature...and to found that edifice on its unavenged tears, would you consent to be the architect on those conditions?"

Fyodor Dostoyevsky, The Brothers Karamazov (Part II, Book V. Pro And Contra, Chapter IV. Rebellion)

"[V]egetarianism is a commendable departure from the established barbarous habit. That we can subsist on plant food and perform our work even to advantage is not a theory, but a well-demonstrated fact. Many races living almost exclusively on vegetables are of superior physique and strength. There is no doubt that some plant food, such as oatmeal, is more economical than meat, and superior to it in regard to both mechanical and mental performance. Such food, moreover, taxes our digestive organs decidedly less, and, in making us more contented and sociable, produces an amount of good difficult to estimate. In view of these facts every effort should be made to stop the wanton and cruel slaughter of animals, which must be destructive to our morals. To free ourselves from animal instincts and appetites, which keep us down, we should begin at the very root from which we spring: we should effect a radical reform in the character of the food."

Nikola Tesla, The Problem of Increasing Human Energy (article in The Century Magazine, Volume 60, May 1900)

"[I]f he be really and seriously seeking to live a good life, the first thing from which [a man] will abstain will always be the use of animal food..."

Leo Tolstoy, The First Step: An Essay on the Morals of Diet, to which are Added Two Stories

"My situation is a solemn one. Life is offered to me on condition of eating beefsteaks. ... My will contains directions for my funeral, which will be followed, not by mourning coaches, but by herds of oxen, sheep, swine, flocks of poultry, and a small travelling aquarium of live fish, all wearing white scarfs in honour to the man who perished rather than eat his fellow-creatures."

George Bernard Shaw, Wagner and Vegetables (letter to The Academy, Oct 15, 1898 (No. 1380))

"I am an old man and have known a great many troubles, but most of them never happened."

Misattributed to Mark Twain