I also really think someone ought to point out:
1. That although there are many
suggestive images, in many cases we don't have enough evidence to be certain that kundalini was meant. (Although in some we do.) -- I'm talking
rigorously certain here.
Greenwell gives the example of
Jiyu Kennett Roshi, an enlightened Zen Meditator, as kundalini, but reading carefully the process is possibly rather different.
We still need to know more, that is, if we care about really looking at evidence. Which we ought to.
2. There
are numerous other energies running through the human soul system apart from kundalini itself.
3. It is
definitely the case that some uses of snake imagery
do not refer to kundalini.
4. This being a thread about
chakras, it is also the case that not every civilization used a chakra system in order get the kundalini to rise, and the ones that did had different ideas about how to use them.
5. It is
not necessarily the case that every culture and every spirituality makes use of kundalini. From our present position this is a
hypothesis... we need to do more work on this before we
know what we are talking about as a species.
And BTW I speak as a confirmed believer in cross-cultural kundalini phenomena. Further:
6. I do know of Kundalini in India, China, Greece, Egypt, Christian systems, and some local/indigenous spiritual groups around the world, and would consider those cases solid. I don't know much about Tibet but I'd be astonished if someone couldn't show that, seeing as how the tradition is live. Also the European alchemical tradition, that's very solid.
7. We know
beyond a shadow of a doubt that kundalini occurs naturally and is not inherently a cultural phenomenon, because it can occur spontaneously in people who know nothing about it, and are not even 'spiritual', as a completely natural upshot of nervous system behaviour.
8. There
are some very intriguing and definite cross-cultural discoveries which show the knowledge of energy and many other things is discovered in parallel rather than simply spreading by word of mouth.
9. We
are beginning to have some definite understanding of the phenomenon from a scientific point of view, both psychological and biological.
But I will end with:
10. There isn't enough definite knowledge available to state for certain 'one true correct' theory of kundalini, even within a tradition much less across them. We are at the beginning of our understanding here, and in order not to shortchange ourselves and to really
know what we are trying to find out, rather than just guessing, we have to admit what we
don't know at present, and be patient as we wait for more info. Something
suggestive does not by any means equal anything
definite. In the meantime,
all lineages in the world that work with kundalini and have a definite system that works are valuable and must continue their work.
All that said, if anyone claimed that kundalini was a miraculous process that totally changes a person, undoubtedly connects them with the divine in the most intimate of manners, absolutely is natural to all of us, certainly is cross-cultural, definitely has an effect on the biology as well as the spirit, explains a great deal of what the hell some traditions have been pointing at for thousands of years, and is absolutely a stunning, amazing, miraculous, spiritual adventure -- no argument from me. And that is pretty good going in itself.