from The Mind in the Cave by David Lewis-Williams (Thames and Hudson) Pages 132-135

Amongst hunter-gatherer (and some other) communities the sort of experience that the Tukano describe is called 'shamanism'. The word describes from the Tungus language of central Asia. Today this is a disputed word. Some researchers feel that the term has been used too generally to be of any use and that it should be restricted to the central Asian communities of its origin. Although I appreciate the point these writers make, I and many others disagree. We believe that 'shamanism' usefully points to a human universal- the need to make sense of shifting consciousness.- and the way in which this is accomplished, especially, but not always, among hunter-gatherers. The word need not obscure the diversity of worldwide shamanism any more than 'Christianity' obscures theological, ritual and social differences between the Russian Orthodox, Greek Orthodox, Roman Catholic and the many other Protestant Churches. Nor does 'Christianity' mask the changes that have taken place over the last two millenia. Too intense a focus is in danger of losing sight of the wood.

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I am not alone in emphasizing the importance of making sense of altered states of consciousness in the genesis of religion.

-snip-

(Weston La Barre states)

...hallucination, trance, possession, vision, sensory deprivation, and especially the REM-dream state- apart from their cultural contexts and symbolic content, are essentially the same psychic states found everywhere among mankind; ...shamanism or direct contact with the supernatural in these states...is the de facto source of all revelation and ultimately of all religions.