But strangely, the oldest encounters of humans with the physical world recapture my hope in humanity, and a sense of wonder about what might be possible in the time ahead of us, this time of climate change.
Let's begin with some of the most ancient of mysteries. The memory of sitting inside Newgrange, a couple of weeks before the winter solstice in Ireland, remains one of the most extraordinary moments of my life; a living mystery to make contact, at least through proximity, with the builders so long ago, who would have stood where I stood in the cosy inner chamber. Why do archaeologists call this place a burial mound, when the passageway within is perfectly situated to capture, on the shortest day of winter, dawn's eastern midwinter light, penetrating the megalithic mound, filling the inside with sun for 17 minutes, a conception that the long nights are now curtailed and summer will inevitably return? Isn't it the rebirth of life? An insemination of light into the earth's womb? The sense of wonder in that place is palpable.
In 1969, a younger Helen O'Kelly witnessed the event when her father discovered the roof box. "He was the first person in about 5,000 years to see it," Helen says, "a very emotional experience, a cultural confirmation of a culture so old." Fascinating, too, that the site was a place identified with Oenghus, the Irish god of love.
When I read once that this "tomb" was enclosed around 3200 BC, I felt a chill go down the back of my neck. For inexplicably, around the same time, the Egyptians started building pyramids, and mummifying, no longer leaving their dead to the western desert. I have no idea what this vague coincidence may mean, but there is something in me that nevertheless feels a sense of wonder. Wonder at the megalithic people on the edge of Europe who would toil away for 20 years building Newgrange, with its scrolling spirals recollecting the movement of the sun above and beneath the earth, and then their near-contemporaries, those serving the sky-climbing pyramids, declaring their compact with time, to endure for millennia. A mystery!
A close enigma is the east-facing Sphinx - apart from its own antiquity, the question of how a layer of erosion, vertical undulations, appears on the body and not the Great Pyramid nearby. Was it rainfall, dating the Sphinx much older than her companions? The geologists' debate about limestone textures is still raging. The outcome shifts the ground from underneath us. Was the Sphinx constructed in 2500 BC, as commonly understood, or much, much earlier, 10,000 BC, when the rains were heavy, and the climate much wetter? Quite a different picture!
The mystery crosses the water. In Egypt, the people built pyramids and travelled down rivers in boats made of reeds, and worshipped feathered serpent gods. Is it merely a coincidence of materials being applied to a similar task in the New World by the Mayans and Aztecs? Is it just that we humans shared a consciousness in those days, Sheldrake's morphic resonance, manifesting either side of the Atlantic?
But one can get lost in these ancient mysteries. I am less fascinated by the possibility of a vanished Atlantis, than amazed by our just extinct cousins, the Neanderthals, a species probably separate from we surviving humans, homo sapiens, encountering each other in Europe during the Ice Age. How would our history have been if the last Neanderthal hadn't died out as recently as 24,000 years ago on the south coast of Spain? What would they have taught us about being human? Human ingenuity? Human emotions, like love and anger? What a bridge that would have been to cross, but now gone, a mystery never to be answered!
The Zanclean Flood, described in 1961 by scientists, was a pre-human event around 5.33 million years ago, an extraordinary breaching of the barrier between the Atlantic Ocean and the dried up Mediterranean Sea. As a one kilometre high waterfall would have begun, the waters apparently dug a 200 km channel across the Straits of Gibraltar, with the dessicated Mediterranean filling up, at its most intense stage, at a rate of about 10 metres a day. How extraordinary! And yet this geologically established, pre-human event is recounted to have happened in earlier times by Pliny the Elder in the first century AD. Now that's a mystery.
If I could do so safely, I would loved to have glimpsed St Brendan on his voyages into the western Atlantic, braving, in his leather-clad boat, the driving seas on his quest for the blessed island.
How similarly wondrous were the Vikings travelling the northern waters, encountering Valhalla-size icebergs, snatching a new life in the absurd extremes of volcanoes and glaciers of Iceland and the longed for vine-lands on the tip of Newfoundland, the last a voyage doubted until confirmed by archaeological discoveries in 1960?
Although confounding, I find these kind of mysteries easy enough to step into. They are cameos, delightful to pick up and play with, and of no apparent consequence.
But now humanity must find a new jump into time, to cross the geological age from post Ice Age Holocene to bypass industrial age Anthropocene and leap into a human shaped sustainable future not yet attained. And in our humble Australia, we are offered an obscure debate between the Leader of the Opposition and the Government about emission schemes and bonuses to polluters that mean little to the average person, and even less to the environmentally aware. The stylish business-as-usual poses can't be understood because they can be barely fathomed, deep down, as to measure up with what's needed. Seinfeld political debates - about nothing - fail to inspire. It is the end of mystery. It is materialism, a debate of non sequiturs.
The noughties were the hottest decade in Australian history. But the facts won't be enough. The political leaders must get past the unedifying minor and marginal promises and try for something better, and deeper. To risk going into the mystery of the gift of life and the marvel of nature.
We have our lives for such a brief moment in time, and the planet is so beautiful. Can't we make the change that's worth remembering, millennia from now - one that touched not just the brilliance to make the necessary changes, but the reverence and wonder we found in nature and some bigger, harder-to-explain story that could explain why we chose to act well?