Philosophers have always had it in for young people. Socrates complained that the young "contradict their parents, chatter before company, gobble up the dainties at the table, cross their legs and tyrannize over their teachers." Back in 1274, Peter the Hermit lamented that the "young people of today think of nothing but themselves." More recent intellectuals have also aimed their wit at young people: the Irish playwright George Bernard Shaw is supposed to have said that "youth is wasted on the young."
When I read these quotes it makes me wonder whether any of these enlightened men ever spent much time with young people. I wonder if they ever came into contact with the passion of youth, with its boundless hope, its selflessness and its enthusiasm.
Or perhaps the world these philosophers wrote about is simply different to ours. Mass education and better nutrition mean the current generation of young people are the smartest the world has ever seen. Average scores on intelligence tests have been rising for decades.
I can attest to this: the young people I am lucky enough to meet during the course of my work as an environmentalist and humanitarian, and ambassador for UN Environment, speak eloquently about the many challenges our world faces. In a world struggling to grapple with some of the biggest crises of any age, this should give us all cause for hope.
Yet there is still much to be done. In response to Bernard Shaw's comment about young people, some answer that "wisdom is wasted on the old." It is easy to find evidence for this: adults have overseen the rise of a number of trends that threaten our way of life -- climate change, air pollution, inequality, the rapid extinction of species and the loss of biodiversity, to name just a few. This has happened on our watch, with adults at the helm.
Thankfully, there are men and women among us who are wise enough to understand the dangers that these and other threats pose. They have worked tirelessly to come up with a global call to action that seeks to tackle these threats.
Known as the Sustainable Development Goals, the objectives laid out in this rallying call for a better future, if met, will roll back the damage done to our planet, our health and our societies.
So it is essential that we pass on the collective wisdom of this plan to our children now for, as they mature and we hand them the baton, they will be the ones responsible for overseeing the success of this monumental task. The sooner they are empowered, the sooner we can start to heal our planet.
As things stand, we will leave our children with a host of environmental problems to clean up. Growing amounts of litter swill around our oceans, entangling and often killing marine animals or making it impossible for them to reproduce. Worryingly, about 20 per cent of coral reefs have been destroyed while a further quarter are at risk of imminent collapse from overfishing and other human activities.
On land, we are destroying forests in ever more inventive ways. These forests provide us with the air we breathe, the water we drink and much of the food we eat. Protecting these forests can help the 1.6 billion people who depend on them for their livelihoods to adapt to climate change. These are vital resources that are quietly vanishing.
To make matters worse, of the 8,300 known wildlife species, eight per cent are already extinct and a further 22 per cent are at risk of extinction. The blame for much of this lies firmly at the feet of humanity: we are degrading the forests where these animals live, we are polluting our oceans and destroying the coral reefs where they thrive, and we are failing to stop the illegal trafficking and killing of wildlife.
The Sustainable Development Goals seek to reverse this damage. They call for urgent action to end the poaching and trafficking of wildlife in all its forms. Elephants and rhinos have become the sad symbols of the slaughter visited on animals by profit-chasing humans, but there are hundreds of other species -- helmeted hornbills, sea turtles, tigers, great apes and my favorite the pangolin -- that are threatened with extinction as a result of human greed and uninformed consumption.
Young people can play a major role in ending this senseless killing. Armed with both passion and knowledge about the wider repercussions of the illegal trade in wildlife -- the devastation it reaps on local economies, the savage loss of the very ecosystems humanity relies on to thrive, young people can demand change. They can urge governments to crack down on the illegal trade, they can push for greater enforcement of the ban on illegal wildlife products, they can demand protection for vital habitats and ecosystems, they can change the traditional belief systems that lie at the heart of some of the most egregious killing. Once empowered with knowledge, this generation will have the best shot yet at reversing some of the most worrying environmental trends.
That is why I believe in the power of young people to make the changes we need to see in the world. Given the necessary tools, they are our great big hope at fighting back against so many of today's ills. If they are to succeed, it is vital that they understand what the Sustainable Development Goals stand for and that they learn how to use these goals to bring about the change the world so desperately needs.
That's why I will host a Lesson Plan as part of the World's Largest Lesson - an astonishing global effort to educate the world's youth about the goals set out in the 2030 Agenda. I will lend my voice to help teachers inform them about Life Under Water (Goal 14) and Life on Land (Goal 15): why ecosystems matter, why biodiversity matters, what happens when we unsustainably use and illegally kill our wildlife.
I hope that through the course of these lessons, which last year reached millions of schools across 160 countries, we can foster their inherent love of the only planet we have and ensure that they never let go of this love as they leave their studies behind.
This world is an awesome place but it needs fresh eyes to defend it. These defenders already walk among us: They are the youth of today, tomorrow's force for change.
This post is part of a series produced by The Huffington Post to mark the occasion of the one-year anniversary of the adoption of the Sustainable Development Goals (SDGs, or, officially, "Transforming Our World: the 2030 Agenda for Sustainable Development"). The SDGs represent an historic agreement -- a wide-ranging roadmap to sustainability covering 17 goals and 169 targets -- but stakeholders must also be held accountable for their commitments. To see all the posts in the series, visit here.