Mouse

"You see these dictators on their pedestals, surrounded by the bayonets of their soldiers and the truncheons of their police. Yet in their hearts there is unspoken--unspeakable!--fear. They are afraid of words and thoughts! Words spoken abroad, thoughts stirring at home, all the more powerful because they are forbidden. These terrify them. A little mouse--a little tiny mouse!--of thought appears in the room, and even the mightiest potentates are thrown into panic."
--Sir Winston Churchill