„Are you a slave? Then you cannot be a friend. Are you a tyrant? Then you cannot have friends.“

— Friedrich Nietzsche
„You cannot friend a hawk, they said, unless you are a hawk yourself, alone and only a sojourner in the land, without friends or the need of them.“
— Stephen King
„If you cannot live alone, you were born a slave.“
— Fernando Pessoa
„You cannot be friends upon any other terms than upon the terms of equality.“
— Woodrow Wilson
„If you want enemies, excel your friends; but if you want friends, let your friends excel you.“
— Dale Carnegie
„Men can have friends, statesmen cannot.“
— Charles de Gaulle
„A friend tells you what you want to hear; a best friend tells you the truth.“
— Marilyn Monroe