This book is a commentary on the Pramana which is the Buddhist logical way of establishing if something is valid or not by the 7th Karmapa.. 

It is the First Chapter of Karmapa Chodrak Gyatso's Ocean ofLiterature on Logi,c and the

Corresponding Chapter from Dha.rmak1rti's Commentary on Validity

"THE SEVENTH KARMAPA CHODRAK GYATSO was a respected scholar, an artist and a realized meditator. He spent much of his life travel- ling throughout Tibet, accompanied by the Garchen or Great Encamp- ment, a huge nomadic community ofmonks, nuns and lay practitioners. During his time, the Garchen reached its peak, numbering 10,000 peo- ple. The community comprised scholars, meditators, a shedra for the study of Buddhist philosophy, and a school of thangka painters, as well as skilled metal workers. The Seventh Karmapa founded an annual Garchen prayer festival which was held during the Festival of Miracles in the First Month of the Tibetan year.

The Seventh Karmapa spent much of his time in private, meditat- ing, teaching, and engaging in scholarly activity, and he has left us several works on both philosophy and meditation. The best known of these are his Indian Texts on Mahamudra, a three-volume collection of spiritual songs and instructional texts on mahamudra meditation by the great mahasiddhas of India, and his Ocean of Literature on Logic, a commentary on the works of Dignaga and Dharmakirti.  --the 17th Karmapa