Anyone who has learned a second language will have made an exhilarating (and yet somehow unsettling) discovery: there is never a one-to-one correspondence in meaning between the words and phrases of one language and another. Even the most banal expressions have a slightly different sense, issuing from a network of attitudes and ideas unique to each language. Switching between languages, we may feel as if we are stepping from one world into another. Each language seemingly compels us to talk in a certain way and to see things from a particular perspective. But is this just an illusion? Does each language really embody a different worldview, or even dictate specific patterns of thought to its speakers?