"Imagine an extrahuman observer looking at us. Such an extrahuman observer would be struck precisely by the uniformity of human languages, by the very slight variation from one language to another, and by the remarkable respects in which all languages are the same. And then he would notice we do not pay any attention to that because for the purpose of human life it is quite natural and appropriate just to take for granted everything that is common. We don't concern ourselves with that, all we worry about are differences."