Respect for Limits
The term limits refers to the finite capacity of the Earth to supply its inhabitants with the things they need for survival, such as clean air, fresh water, food and the ability to recycle waste and preserve the health of the planet's biodiversity. This idea is foundational in in the broad sustainability discourse and is referenced often in the sustainability literature.
For the last several centuries, we have been converting and dispersing the energy stored in resources like coal, and petroleum in ways that make it unavailable for use by future generations. Because we live in a closed system that is governed by the laws of thermodynamics, some of that matter and energy returns to the Earth, some of it is dispersed in forms that we consider waste, for example as excess heat, and some of it is released into the atmosphere. At the beginning of the twentieth century, when there was 1 billion people on the planet, matter and energy were being converted and dispersed at a much slower rate than is occurring now that the world human population is nearly 7 billion. As population growth accelerated in the last century, so did the rate of our dispersion of matter and energy.
When we move from the perception of the Earth as an unlimited store of resources to a perception of Earth as finite, we begin to think differently about our relation with other humans alive today, our responsibility to future generations, our relationship with other species, and our own needs and wants. A the same time, the concept of limits and the broader idea of respect for limits is potentially troublesome because it reflects a fundamentally different way of thinking about our own behaviors and beliefs. The idea of respect for limits also runs counter to the dominant economic model in most of the world today, which is based on the assumptions of unlimited capacity and unlimited growth. That “no respect for limits” model sees consumption as social responsibility if not a patriotic duty. Education for sustainability helps learners develop new ways of seeing the world, and new strategies for analyzing their own consumption habits that are more in line with the finite limits of the natural world.