"But I get puzzled about the "oneness with nature" mullarkey. What evidence can there be that there was once such an attitude?"
It's a good question, and I'm going to answer:
We accept that our ancestors are different from us in ways that are measurable. One way to measure this difference is by comparing our 'developed' lifestyle and psychological/spiritual processes with people that even today continue to live a neolithic life.
In my mind, the most apparent and immediate difference is the observable relationship between the people and the land in which they live. In considering Australian aboriginal life (traditional), we can see that landforms are believed to be the marks of their ancestors. 'Dreamtime' and the landscape are woven together, indivisible, and existing together on differing levels of consciousness. Non more or less real than the other. This is a giant leap for the modern mind to make. Another example is the shamanic ability to become the animal that is hunted, in a very real and spiritual sense. This is a profound aspect of the linked psychology/spirituality between the ancient homo-sap and the land in which s/he LIVED with a capital LIVED. Anyone who spends a freat amount of time outdoors, relatively unshielded (in a psychological way moreso than physical) from the processes of growth, death and change apparent on every level of being and every second of life, can ONLY come to a point where the sense of 'belonging' occurs. In no way do I mean crystal-gazing and knitting muesli; I mean a fundamental baseline cognition of the struggle and changing balance of the processes of birth growth and death, and the interconnectedness of all. This has been approximated by modern humans more out of wishful thinking and an inherent belief in a 'golden age', or a golden state, like a cross between Dr Doolittle and Mrs Woo-Woo/Hiawatha, which in so so many ways has just assisted the dehumanising effect on tribes and peoples that still share a more than commensal relationship with the land on which they and their ancestors have nurtured, hunted, fished and picked.
'being at one' is, I think, crap. But not because I can't imagine or haven't felt part of the whole thing, a microcosm within a macrocosm, which I do. It's not until I felt the great nothingness, the umbra nihili thang, the complete sense of passive smiling agape (insert word for which there is no word) in the flow of time and decay, that I ever felt 'one', and it was spelled with a zer0 not an open mouthed 'O'.
As for evidence that there is such 'malarkey' as living at one with nature, we all eat food that's grown in the earth, we all walk on the earth, swim in and drink the water, posses within us the Elements, etc etc. I'd argue that nothing has changed other than our perceptions and the varying degrees of 'shielding' from necessary responsibility towards our environment. The experential gap is so wide between the factory worker and the ancestor that we have to look towards Amazonia, Irian Jaya, etc etc.
http://www.learn.co.uk/default.asp?WCI=Unit&WCU=26816
Perhaps check the link and argue the evidence AGAINST (i.e) the Sioux ever having experienced 'one-ness' with nature? Bearing in mind that 'one-ness with nature' meant living and dying by it, just as we do now, albeit once being immeasurably more aware of the process, and actually bearing the responsibility for poisoning the river etc.
