In the past many scientists and economists presumed we were purely rational beings, self-promoting our own interests with perfect knowledge of the consequences of our actions. These assumptions are really influential: many world governments rely on our self-interest and perfect decision-making to change our behaviour, hoping rational arguments and penny-savings will alter our trajectory towards crisis.
Why is democracy the secret for sustainability? Two reasons: 1) it allows the majority of good sensible people to stop the unsustainable ones; 2) its makes sure that people feel they have the ability to make change, because without the ability to make change people see being sustainable as futile and give up - paradoxically ensuring what they hoped to avoid!
Sites in Turkey, including the famous Gobekli Tepe, show that before agriculture, hunter-gatherers started harvesting wild grasses. They were using the ancestors of wheat and barley to make beer - crushing them up in big tubs and leaving them to ferment. They found hundreds of these tubs and even simple musical instruments. What were they doing - having a festival of course. At this proto-Glastonbury hunter gatherer groups would come from miles around to drink, listen to someone rock out on the deer-horn flute and enjoy themselves.