The history of man has been influenced by many revolutions, but none more important that the Agricultural Revolution, followed by the Industrial Revolution. We are now at the threshold of a third great revolution, the transition to a sustainable society, which is described as "one that meets the needs of the present without compromising the ability of future generations to meet their own needs."

There is a profound moral question that revolves around the issue of how we treat the life-giving resources of the planet. Do we who are here today owe anything to future generations of people and other living things?

If your answer is in the negative, as current and past practices would seem to indicate, then we are squarely on course traveling down the road to massive environmental degradation.

If, however, we have a moral obligation to the future, then we must move expeditiously to preserve all environmental options for those who will follow.

At this point in history, no nation has managed, either by design or accident, to evolve into a sustainable society. We are all pursuing a self-destructive course of fueling our economies by consuming our capital — that is to say, by degrading and depleting our resource base — and counting it on the income side of the ledger.

That obviously is not sustainable over the long term.

The bottom line question is obvious and critical. Can we as a nation evolve into a sustainable society during the next four or five decades? That is to say, a sustainable society which we would view with approval?

The answer is yes — if we have strong political leadership and the support of a society imbued with a guiding environmental ethic. The evolution of such an ethic within our culture is happening now at an accelerating pace.

Increasingly, we have come to understand that the wealth of the nation is its air, water, soil, forests, minerals, rivers, lakes, oceans, scenic beauty, wildlife habitats and biodiversity. Take this resource base away and all that is left is a wasteland.

Fortunately, there are encouraging signs that we as a society are beginning to develop a conservation ethic that will ultimately flower into a powerful social, political and economic force. The sooner the better.

Once we have nurtured a generation that understands the basic nature and functioning of our life-sustaining ecosystem, a generation that recognizes that all creatures including humans are sustained by the same ecosystem, a generation that appreciates its role and impact on that system, from that, of necessity, will evolve a guiding environmental ethic. That is the way it works.

An ethic evolves when a society reaches a firm consensus that certain conduct enhances the welfare of the group and other conduct endangers it.

This ethic will guide leaders in both the private and public sectors in making the hard decisions and it will provide the necessary public support to implement them. Without such a guiding ethic, we won't make the hard decisions until necessity overwhelms us, and then it's too late.

In a speech in Philadelphia on June 27, 1936, President Roosevelt said: "There is a mysterious cycle in human events. To some generations much is given. Of other generations much is expected. This generation of Americans has a rendezvous with destiny."

This eloquent exhortation is better fit for the generation which is now preparing to assume responsibility for our common future. The challenge of forging a sustainable society during the next few decades will require that we contemplate a bigger rendezvous and a bigger destiny than Roosevelt was thinking out in 1936.

We can measure up to the challenge if we have the will to do so — that is the only question.

— Gaylord Nelson