The present generation of well-informed translators are doing the world a great service as they continue to bring the great texts of Buddhist philosophy to us. This is an authoritative translation of one of the greatest philosophical works of all time, which has never before been available in English. About one thousand years ago it took hundreds of years for the Tibetans to translate the early Buddhist works into the Tibetan language. Now, following the Tibetan diaspora that was forced by the Chinese invasion of Tibet, the center of humanity's philosophical consciousness is relocating to the English speaking world. It is now more than one hundred years since the early English translators managed to produce translations of marginal quality. The present generation of translators is providing not only great translations, but also well-informed commentary. This is a great gift to humanity. Thank you.