Ehrlich and Ehrlich


"Valuable as ecosystem goods are however, they are increasingly being replaced by goods from human managed systems"

p. 197


"replaced by goods from human managed systems" that create a tragedy of the commons.


"Energy is a key concept" --is "the ability to effect change in our physical world."


"Matter is just another form of energy"


"The rule that energy can neither be created nor destroyed is the famous 'first law of thermodynamics.'"

p. 176

Consumption           (is related closely to the "A" variable in I = PAT formula)

            We face a series of entwined dilemmas

            these are ecological in character and arise form social conditions

                        numbers and density of people

                        patterns of consumption

                        susceptibility to epidemics

                        distribution of basic resources




p. 232

"The continued failure to ask what humans really want...

            the poor a better level of living

                        .... could endanger the well being of even the rich


                                                debilitating costs

                                                continuous resource wars

p. 233

Classes of problems

These are socially created ecologically consequential matters that are converging:

            1). That class of problems that have no technical solution:

                        "freedom to breed in a commons is intolerable."

                                                                                                Garrett Hardin


            2). That class of items that have no economic value:

                        "A tree has no economic value until it is cut down."

                                                                                                Gloria Steinham

Trees do not a forest make.

            a tree – pumps water, transforms radiation into oxygen, holds the soil, shades

            forests  are watershed buffers, source of springs, wildlife, renewable carbon bank


Any forest is an association of mutualistic soil bacteria and plants, tied to commensal soil fungi, lichens, and animal life that survives in unison withstanding long-term climatic variations, periodic weather disruptions, intermittent fires, and regular depletion of nutrient conditions due to a means of compensation that often escapes the market value of lumber, or hunting preserves, or even protection of steep slopes as insurance against floods.