it's possible for pro-choice people to make significant contributions to the cause of animals, just as some pro-choice feminists have also advanced the cause of feminism.

Animal rights, as a secular, moral philosophy, may appear to be at odds with traditional religious thinking (e.g., human "dominion" over other animals), but this is equally true of democracy and representative government in place of the divine right of kings, the separation of church and state, the abolition of human slavery, the emancipation of women, birth control, the sexual revolution, LGBT rights, and perhaps all social progress since the end of the Dark Ages and the beginning of the Age of Enlightenment.

Some of the greatest figures in human history have been in favor of ethical vegetarianism and animal rights. These include: Albert Einstein, Leonardo da Vinci, Leo Tolstoy, Mohandas Gandhi, Alice Walker, George Bernard Shaw, Robert Browning, Percy Shelley, Voltaire, Thomas Hardy, Rachel Carson, Harriet Beecher Stowe, Victor Hugo, John Stuart Mill, Jean-Jacques Rousseau, Pythagoras, Susan B. Anthony, Albert Schweitzer, Isaac Bashevis Singer, Gertrude Stein, Frederick Douglass, Francis Bacon, William Wordsworth, the Buddha, Mark Twain, and Henry David Thoreau.

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