The Tibetan tradition emphasizes the study of the sixteen characteristics of the Four Noble Truths, as described in the Abhisamayalamkara. The Mahayana text Ornament of Clear Realization (Abhisamayalamkara) identifies four characteristics of each truth, for a total of sixteen characteristics, which are presented as a guide to contemplating and practicing the four noble truths.[1] The Ornament of Clear Realization is a key text in the curriculum of Tibetan Buddhist monasteries and study colleges, and this method of study and practice is emphasized in the Tibetan tradition.
impermanence - the five aggregates are impermanent and change from moment to moment
suffering - the five aggregates have come into being because of avidya (ignorance) and kleshas (disturbing emotions), and they are under the influence of the avidya and kleshas
emptiness - there is no "self" outside of the five aggregates that controls or makes use of the five aggregates
selflessness - there is no "self" to be found within the five aggregates that controls or makes use of the five aggregates
These characteristics refer to karma, kleshas, and avidya (ignorance)[4]
causes - karma, kleshas, and avidya are constantly arising within our mental continuum, and because of their nature they have the quality of being the causes of suffering.
origin - kleshas and karma are the actual origin of suffering, not just intermediate links.
strong production - avidya, kleshas, and karma act forcefully as the main causes of suffering (they are not just passive ingredients)
condition - avidya, kleshas, and karma are more than just the main causes of suffering, they are also the contributory causes