The language we speak shapes how we think. But the way we think also shapes the language we speak, and the way we live shapes both language and thought. When we encounter or create new ideas, we can usually describe them with new combinations of old words. And if not, we easily adapt or borrow or create the new words or phrases we need. As Edward Sapir once put it, "We may say that a language is so constructed that no matter what any speaker of it may desire to communicate...the language is prepared to do his work." So in its common interpretation, which sees a list of dictionary entries as determining the set of available thoughts, this proposition is false.