 The claim that the Hopi lack our concept of time has not stood up to scrutiny. Whorf used clumsy translations of Hopi speech that concealed the extent to which they talk about time (references to yesterday, tomorrow, days of the week, lunar phases, etc.). More interestingly, Whorf provided no direct evidence of how the Hopi think. Instead, he used the circular reasoning that they don’t think about time as we do because they don’t talk about time as we do. In fact, the Hopi use numerous familiar devices for time keeping, such as calendar strings and sun dials, and their sensitivity to time is evident a wide variety of cultural practices (Pinker 1994).