There are several different 'transmissions' that I know of.
The first is a 'lung' (rhymes with 'tune'). That is a simple reading of something, say a text, that breathes life into it, so to speak. A text by itself is considered sterile, but having a living person read it to you, that had it read to him, etc., on back to the origin of the text, brings it alive. The only requirement for the person reading it is that they've had it read to them by someone in the chain.
A 'wong' (rhymes with 'song') is totally different. (a.k.a. Skt.: Abisheika, English: Empowerment) It is given in for a specific meditation, not just a text, and the preceptor has to not only received it from someone else, but they've had to do a retreat and accomplished the practice to (at least a minimal degree) before they can give the initiation to someone else.
'Direct introduction' is another. I'm not going to talk about that.
There's more to it than that, but that is the Reader's Digest version of the idea. Take that as a initial understanding and be ready to modify it as you get more of an education in it.
Last edited by smcj
on Thu Jun 13, 2013 7:21 pm, edited 1 time in total.
There is a tradition of making a distinction between two different perspectives on the nature of emptiness: one is when emptiness is presented within a philosophical analysis of the ultimate reality of things, in which case it ought to be understood in terms of a non-affirming negative phenomena. On the other hand, when it is discussed from the point of view of experience, it should be understood more in terms of an affirming negation.