An interesting and sometimes perplexing word worth shedding some light on involves the very notion of “light.” The term ösel (Tib.’od gsal) literally means “clear [sel] light [ö],” and there are many who translate it this way. “Clarity” is another popular rendering. The Vidyadhara, however, preferred “luminosity,” which points not so much to the light itself, but to the quality or state of being radiant. He once remarked that even though the experience of brightness, the vividness of the phenomenal world, was an important experience on the path, it wasn’t in itself ultimately the point. Beyond that, as Thrangu Rinpoche once remarked, luminosity comes to mean the basic “knowing” quality of mind in which nothing is excluded.
In his oral commentary on Pointing Out the Dharmakaya, Thrangu Rinpoche makes the following comments on ösel and shunyata in discussing “the dharmata nature of mind”:
While it is empty and while there is nothing there in a sense, nevertheless there is a natural clarity or luminosity, which is traditionally referred to as buddha nature, the spontaneously present qualities, and so on. Here luminosity does not refer to physical light or some kind of physical radiance. In this context, luminosity simply refers to the cognitive capacity or awareness, which is the defining characteristic of a mind. A mind is not any thing, and yet it cognizes; that is what is meant by the unity of luminosity and emptiness. This is something that we experience directly and that we do not have to talk ourselves into through logical analysis.