Sustainable development generally has been defined as development that meets the needs of the present without compromising the ability of future generations to meet their own needs. According to Paul Hawken, author of The Ecology of Commerce, "sustainability" is an economic state where the demands placed upon the environment by people and commerce can be met without reducing the capacity of the environment to provide for future generations. It can also be expressed in the simple terms of an economic golden rule for the restorative economy: take no more than you need, try not to harm life or the environment, make amends if you do, and leave the world better than you found it.
Sustainability relies on a deeper understanding of the world and the economy. Many people will agree that the earth is resilient and that humans behave arrogantly in believing we have the power to destroy the earth. Sustainability thinkers instead consider the economic state of survival as a part of future generations. For example, studies have shown that if it cost five or ten times more to heat our homes, obtain drinkable water, or fill-up our automobiles, this will have an obvious detrimental effect on economic development and thereby effect the quality of life.