In pre-industrial societies such as fifteenth-century Tibet, the composition of texts was a time-intensive and laborious process. There were few potential readers for works like Tsong kha pa bLo bzang grags pa’s (1357-1419) Great Exposition of Secret Mantra (sNgags rim chen mo),1 as literacy was primarily confined to the monastic universities, and scholastics like Tsong kha pa generally had no professional stake in composing texts. Successful completion of a text on religious philosophy and practice like the Great Exposition had no bearing on tenure or promotion, and authors received no royalties. Moreover, Tibet had inherited from India a huge corpus of canonical and extra-canonical texts, which encompassed the entire range of Buddhist philosophy and practice, as well as such fields as art, architecture, music, and medicine. Because of the high regard Tibetans had for the texts they had imported from India, only indigenous works considered to be significant contributions to Buddhist studies were widely read. The libraries of Tibetan monastic universities have thousands of books by both Indian and Tibetan authors that never caught on and are seldom if ever read, and the odds were generally against any particular text’s gaining a wide readership.