A mountain slope four hours journey from a parking lot, however, poses a different set of realities. Not long ago, while on such a hike, I had time to ponder how human health depends on a healthy environment – what is healthy for the planet is healthy for the person, and its converse, what is healthy for the person is healthy for the planet.

All of us know that our very lives depend on a healthy planet. The oxygen we breathe is exhaled by vegetation, most of it from microscopic plants in the oceans. The nitrogen which builds our proteins is extracted from the air by bacteria. Indeed, a small number of bacteria species are the only living things which can take this gas out of the atmosphere, and change it to a form which higher organisms can utilize. Without these microbial creators there could be no ecosystems above the microscopic level anywhere on Earth.

The previous examples are just two illustrations of humanity’s dependence upon the biosphere, and there are of course, many more. However, there are also more subtle interactions. The conditions under which a living thing can survive are much broader than those under which it can thrive. Our rapidly changing world of technology is moving us farther and farther from the environment for which our evolution has designed us. How many of our medical, social and psychological problems are a result of these shifts? The kinds of stimulation our ancestors received from the myths of the storyteller are now replaced by the sensory overload of the multiplex screen. The flavours of our food are chemically enhanced. So many of our needs are artificially altered in similar ways.

Studies have shown that mental health improves when people have access to nature. The rapid growth of the ecotourism industry attests to our desires for such access. On sunny weekends the trails are congested with hikers, mountain bikers and dog walkers, and parking lots are filled to capacity by early afternoon. Thrity years ago I could visit those same trails almost in solitude. As the increasing complexity of society removes us farther from our origins the need to reaffirm those origins is also increasing.

What is healthy for the person is also healthy for the planet. Biological systems consist of many feedback loops. The attraction we feel for nature is one such loop. When people visit healthy ecosystems they begin to respect and preserve those places. When they learn about the ecology of those same places the respect increases even more. The greater the numbers of people who identify with nature the greater the ability to protect nature. Critical mass is not just a requirement for nuclear reactions, it is also a requirement for political and social reactions – the capacity to change the values and directions of a society. Such a shift began in the late 1960’s with the beginning of the environmental movement, but its success has been limited. The critical mass of support for successful environmental change has not yet been attained.

How do we distinguish a healthy from an unhealthy environment? The answer to that question is far from straightforward. For one thing there is a need for ecosystem translators – people who have such knowledge, but also have the ability to present it in a form which can be understood by people without scientific training. There is also the need to convey the wonder and mystery of nature as well as the technical information. Some of the most marvelous of those wonders are the complex inter-dependencies of living things. One of those complex relationships involves forests and fungi. Trees require special kinds of mushrooms to survive. These organisms deliver water and essential nutrients to tree roots. Anything which is unhealthy for the mushrooms also affects the health of the trees. For example, air pollution adversely affects a tree’s vitality. However, it also affects the vitality of the mushrooms, increasing the problem even more. Knowledge such as this is well known to scientists but has not been conveyed to the rest of society.

An understanding of the Earth and its wonders should not be esoteric wisdom, but unfortunately it is. Many people believe that such understanding is too complex for them to comprehend, but that is not true. All branches of knowledge have a gradation from simple to complex. Most of us can drive a car, but only a few can operate a semi-trailer. There are many courses available on such practical skills as computer training, but few which teach an appreciation of the natural forces upon which our entire survival depends.

Buy a pair of hiking boots, purchase a wildflower guide and visit your local woodland. The exercise will contribute to your physical well-being, and visiting the outdoors will also contribute to your mental well-being. In return for what you have received, do something to help preserve the Earth’s wild places which are doing so much to preserve you. Join a local naturalist club, and teach your friends what you have learned, or support a wilderness conservation campaign.