Mostly green

Perhaps its the death instinct in me, but I'm drawn toward scenarios of impending doom. My favourite until recently was the melting Siberian permafrost releasing billions of tons of methane into the atmosphere with, as usual, unknown consequences.
How much do scientists really know? They can be paid to prove anything. Or at least produce research that indicates anything.
Today I read in the Telegraph that in ten days time the worlds largest ever non-military experiment will commence, somewhere on the Swiss-French border, which is designed to replicate the conditions which existed seconds after the big bang. Its called a Large Hadron Collider, and is costing £4.4 billion. My initial thought was "sounds a bit like half-life". But it could be worse than that, according to Otto Rossler, who says the proton collisions caused by this machine could create "mini black holes" which could destroy the earth. CERN say its perfectly safe, don't worry.
Sometimes it seems to me we're balancing on the edge of a precipice, daring it to swallow us up. No-one is in charge. We, as a species, collectively, want to die.

I read in the Telegraph the other day that the UK is set to become the most populous nation in Europe in about 50 years time. We currently have over 60 million people, which makes us environmentally unsustainable, according to the Optimum Population Trust, who reckon we could possibly support about a third of that figure, if we we lived a bit greener.
And I remember reading the words of a North American Indian, in Dee Brown's Bury My Heart at Wounded Knee, expressing incredulity at the white man's destruction of the earth. They/we kill everything for short term gain, thinking there'll be something else around the corner. It's surely very stupid, basically unsustainable, so why are we still doing it?
I suppose we don't know how to stop. Personally I don't know what "sustainable" means. I don't know how much land I would need to support myself, and the thought of scrabbling in the earth and maybe killing the odd rabbit isn't very appealing for me. Well, it's slightly appealing.
Am I missing something? Or are we all in total myopic denial?
I'm trying, a little bit. I have no car, no kids, and haven't bought any meat for a while now. I'll eat meat if I find some or am given some, but I hate to support factory farming. I'm appalled by human cruelty, both to our own and others species, and wonder about the cause of this.
We're genetically aggressive perhaps, or passive/aggressive, i.e. we're herd creatures who follow the loudest and angriest of our fellow creatures.