What will it take?

Let's face it; the global economy sucks, the weather patterns are being altered, surpopulation is overloading the planet's resources.
Not only most of the human population seems to be blisfully ignorant of the damage we are causing our environment, but those who do know are not helping matters much.

What will it take to make humans change course and adopt a rational way of living?

Reasoning with or educating people is a waste of time if you try to apply it globally. Too many cultures are indifferent or plain hostile to new ideas. As you well know, any average person will not move unless his life is in emminent danger.

Of course, the cause of all this global misery is selfishness. Everyone wants to be happy and free of suffering. And happiness in this age is defined by consumerism; get as many things as you can before you die. It doesn't matter if you really need it or not, the ones selling the stuff WILL TELL YOU WHAT YOU NEED!
And since most people are too lazy to do the research for themselves, even with today's internet resources, don't count on people to educate themselves about the worthiness of consumer products.

The solution is simple; first everyone has to understand what their basic need are:
1- Food
2- Clothing
3- Shelter.

Everything else is luxury. Food includes clean air to breathe, clean water to drink, healthy food to eat. Clothing is what you need to keep healthy, not to look good in the eyes of others. Shelter is to be adapted to local climate and seasons for the purpose of providing a safe space to sleep, eat and support a family.

Nothing exceptional here. But somehow humans got so lost in superfluous stuff that they are destroying natural resources at an unprecedented speed in the history of this planet.

Why? It seems that in humans, having enough is never enough. Look at the diet of north-american average Joe's, way above what is life sustaining. Double or triple the amount of calories needed is swallowed every day. They just can't stop eating.
How many shoes do you own? Yet how many can you wear at any one time? Answer: you can only wear one pair at any one time, so what's the use of owning 10? 20? 2000?
Same goes for everything fashionable. If the neighbour happens to buy the latest lawnmower, you can be sure those living around him will soon get one too, even if the old one is only 1 year old. Ridiculous.

But that's just me it seems, when I start talking like this to people, I get the "look", as if I'm a lunatic. That's the selfishness again. People simply have brains that are wired so that only the things that interest them personally get's past their senses into consciousness. Everything not immediately threatening to their lifes is simply ignored.

As I always say; Nature will take care of herself, even if it means the destruction of everything we have built.