"Of all the creatures, man is the most detestable. Of the entire brood, he's the one that possesses malice. He is the only creature that inflicts pain for sport, knowing it to be pain. The fact that man knows right from wrong proves his intellectual superiority to the other creatures; but the fact that he can do wrong proves his moral inferiority to any creature that cannot."

- Mark Twain, American Novelist

"The assumption that animals are without rights, and the illusion that our treatment of them has no moral significance, is a positively outrageous example of Western crudity and barbarity. Universal compassion is the only guarantee of morality."

- Arthur Schopenhauer, German Philosopher

"These birds and animals and fish cannot speak, but they can suffer, and our God who created them, knows their sufferings, and will hold him who causes them to suffer unnecessarily to answer for it. It is a sin against their Creator."

- George Q. Cannon, Animal Activist