Change is never easy, and it often creates discord, but when people come together for the good of humanity and the Earth, we can accomplish great things.

The future doesn't exist. The only thing that exists is now and our memory of what happened in the past. But because we invented the idea of a future, we're the only animal that realized we can affect the future by what we do today.

If we pollute the air, water and soil that keep us alive and well, and destroy the biodiversity that allows natural systems to function, no amount of money will save us.

We're in a giant car heading towards a brick wall and everyone's arguing over where they're going to sit.

The human brain had a vast memory storage. It made us curious and very creative. Those were the characteristics that gave us an advantage - curiosity, creativity and memory. And that brain did something very special. It invented an idea called 'the future.'

I can't imagine anything more important than air, water, soil, energy and biodiversity. These are the things that keep us alive.

The human brain now holds the key to our future. We have to recall the image of the planet from outer space: a single entity in which air, water, and continents are interconnected. That is our home.

There are more humans than all of the rabbits on earth. There are more of us than all the wildebeests, than all the rats, than all the mice. We are the most numerous mammal on the planet. But because we're not like rabbits or rats or mice, we have technology, we have a consumptive appetite, we have a global economy.

We humans have become dependent on plastic for a range of uses, from packaging to products. Reducing our use of plastic bags is an easy place to start getting our addiction under control.

Ultimately we need to recognize that while humans continue to build urban landscapes, we share these spaces with others species.

With the world's human population now at seven billion and growing, and the demand for technology and modern conveniences increasing, we can't control all our negative impacts. But we have to find better ways to live within the limits nature and its cycles impose.

Nature surrounds us, from parks and backyards to streets and alleyways. Next time you go out for a walk, tread gently and remember that we are both inhabitants and stewards of nature in our neighbourhoods.

Doing all we can to combat climate change comes with numerous benefits, from reducing pollution and associated health care costs to strengthening and diversifying the economy by shifting to renewable energy, among other measures.

Our personal consumer choices have ecological, social, and spiritual consequences. It is time to re-examine some of our deeply held notions that underlie our lifestyles.

The damage that climate change is causing and that will get worse if we fail to act goes beyond the hundreds of thousands of lives, homes and businesses lost, ecosystems destroyed, species driven to extinction, infrastructure smashed and people inconvenienced.

Just as fossil fuels from conventional sources are finite and are becoming depleted, those from difficult sources will also run out. If we put all our energy and resources into continued fossil fuel extraction, we will have lost an opportunity to have invested in renewable energy.

Scientists have been warning about global warming for decades. It's too late to stop it now, but we can lessen its severity and impacts.

The medical literature tells us that the most effective ways to reduce the risk of heart disease, cancer, stroke, diabetes, Alzheimer's, and many more problems are through healthy diet and exercise. Our bodies have evolved to move, yet we now use the energy in oil instead of muscles to do our work.

Education has failed in a very serious way to convey the most important lesson science can teach: skepticism.

We need love, and to ensure love, we need to have full employment, and we need social justice. We need gender equity. We need freedom from hunger. These are our most fundamental needs as social creatures.

The increasing frequency of extreme weather events, droughts and floods is in line with what climate scientists have been predicting for decades - and evidence is mounting that what's happening is more severe than predicted, and will get far worse still if we fail to act.

Rapid population growth and technological innovation, combined with our lack of understanding about how the natural systems of which we are a part work, have created a mess.

Conserving energy and thus saving money, reducing consumption of unnecessary products and packaging and shifting to a clean-energy economy would likely hurt the bottom line of polluting industries, but would undoubtedly have positive effects for most of us.

Some solutions are relatively simple and would provide economic benefits: implementing measures to conserve energy, putting a price on carbon through taxes and cap-and-trade and shifting from fossil fuels to clean and renewable energy sources.

We must pay greater attention to keeping our bodies and minds healthy and able to heal. Yet we are making it difficult for our defences to work. We allow things to be sold that should not be called food. Many have no nutritive value and lead to obesity, salt imbalance, and allergies.

We must reinvent a future free of blinders so that we can choose from real options.

In the environmental movement, every time you lose a battle it's for good, but our victories always seem to be temporary and we keep fighting them over and over again.

My parents survived the Great Depression and brought me up to live within my means, save some for tomorrow, share and don't be greedy, work hard for the necessities in life knowing that money does not make you better or more important than anyone else. So, extravagance has been bred out of my DNA.

The voluntary approach to corporate social responsibility has failed in many cases.

We have much to learn by studying nature and taking the time to tease out its secrets.

Planting native species in our gardens and communities is increasingly important, because indigenous insects, birds and wildlife rely on them. Over thousands, and sometimes millions, of years they have co-evolved to live in local climate and soil conditions.

I've always been more interested in organisms that can move on their own than in stationary plants. But when I canoe or hike along the edge of lakes or oceans and see trees that seem to be growing out of rock faces, I am blown away. How do they do it?

I always felt that if someone shot me, it would be great for the environmental movement, because they would make me a martyr. Our biggest fear was our children, because there was a tremendous amount of threat and intimidation, and my wife was terrified that the children might be grabbed or assaulted in some way. That was the real fear.

Canada should always open its doors to those who are oppressed or in cases of emergency. When Canada offered refuge to 50,000 boat people in Vietnam in the 1970s, I was particularly proud to be Canadian.

We pride ourselves on our democratic traditions, but in Canada, women couldn't vote until 1918, Asians until 1948, and First Nations people living on reserves until 1960.

Global trade has advantages. For starters, it allows those of us who live through winter to eat fresh produce year-round. And it provides economic benefits to farmers who grow that food.

The truth is, as most of us know, that global warming is real and humans are major contributors, mainly because we wastefully burn fossil fuels.

If we have any hope of finding ways for seven billion people to live well on planet with finite resources, we have to learn to use our resources efficiently. Plastic bags are neither efficient nor environmentally friendly.

Just as human activity is upsetting Earth's carbon cycle, our actions are altering the water cycle.

The government's desire to expand global trade may be understandable, but we mustn't give away too much. We must tell our elected representatives to at least delay the Canada-China FIPA until it has been examined more thoroughly, and to reconsider the inclusion of investor-state arbitration mechanisms in all trade deals.

One of the joys of being a grandparent is getting to see the world again through the eyes of a child.

Over and over, we hear politicians say they can't spend our tax dollars on environmental protection when the economy is so fragile.

Because countries often have differing political and economic systems, agreements are needed to protect those invested in trade.

We can't blame children for occupying themselves with Facebook rather than playing in the mud. Our society doesn't put a priority on connecting with nature. In fact, too often we tell them it's dirty and dangerous.

My earliest memory from childhood is of fishing with my father. And I remember vividly we were in a store, and we were buying a pup tent to go on our first camping trip.

More than a billion people lack adequate access to clean water.

Think about a seed. Once it lands, it's stuck. It can't move to find better soil, moisture or sunlight. It's able to create every part of itself to grow and reproduce with the help of air, water and sun.

Our beliefs, our values shape the way we look out at the world and the way we treat it. If we believe that we were here, placed here by God, that this - all of this creation is for us, it's for us to go and occupy, dominate and exploit, then we will proceed to do that.

Japan is a model already to the lie that economic growth is the key to our future. If they can really show an alternative to nukes and fossil fuels, then they will be the poster boy for the renewable energy for the future.

Too often, governments are quick to use excessive force and even pervert the course of justice to keep oil and gas flowing, forests logged, wild rivers dammed and minerals extracted. As the Global Witness study reveals, citizens are often killed, too - especially if they're poor and indigenous.