Pure time preference is a preference for something to come at one point in time rather than another merely because of when it occurs in time. In opposition to Sidgwick, Ramsey, Rawls, and Parfit we argue that it is not always irrational to be guided by pure time preferences. We argue that even if the mere difference of location in time is not a rational ground for a preference, time may nevertheless be a normatively neutral ground for a preference, and (...) this makes it plausible to claim that the preference is rationally permitted. (shrink)