[link] , [link] , and [link] do not convey the full picture of the life cycle of a microscosmic society as it is now known, for they do not follow developments far enough into the future.
If the life cycle of the microcosmic Drosophia and yeast populations are similar to the human cycle of population and societal growth, then the former confirms our explanation of the cause of the deviation from exponentiality of the population growth of the United States) shows that it is essentially inevitable, and promises analogous declines in growth rate and asymptotic approach to stable maximum states for world population and possibly for energy consumption, productivity, growth of knowledge, etc., as well.
Equillibrium state
It is not difficult to envision this equilibrium state and its corresponding equilibrium society as a paradise) finally freed from the pressures and problems created by incessant population growth and its derivative phenomena, and granted the option to accommodate its desires to its means in a gradual evolutionary manner. But such a society would, necessarily, differ greatly from that to which we have become accustomed, in which savings bank deposits and corporate income offer fixed annual fractional returns by some fiducial duplication of the theological miracle of the creation of substance and value from null and void. The equilibrium society apparently promised by the Drosophila and yeast civilizations will necessarily be one of decreased personal and social mobility, decreased personal opportunity, and no doubt of decreased excitement. Each of us will have different views of the desirability of such stable circumstances.
[link] , [link] , and [link] paint, in fact, too cheerful a picture of the population life cycle of microcosmic societies, and by implication, of our own potential future, for they do not follow developments far enough into the future. They misleadingly present the impression that an ultimate stable state of maximum population is attained by gradual increase from earlier states; they carry the implication that once society has adapted to the relatively rapid and critical conversion from exponential growth, displayed, for instance, from hours 7 through 12 in [link] , a uniform and hence rather crisis-free period of unlimited duration will follow --- a period perhaps bland, possibly undesirable in certain aspects, but one at least stable. Unfortunately this is not the case, for the same forces which worked to constrain and limit exponential growth, converting it into a type of growth which is subject to an absolute upper bound as displayed in [link] , [link] , and [link] , continue to work even as population closes upon the maximum value.
Pollution
In the microscosmic societies these forces of constraint are imposed, on the one hand, by the geometrical restraints of the finiteness of the environment, pint bottle or Petrie dish; and on the other by the related twin factors of resource depletion and non-absorption of the byproducts of metabolism, which we generally will interpret for our more complex situation as “pollution”. Whereas the direct effect of the finite environment is the absolute limitation of population, the ultimate effect of resource depletion and increasing pollutant density is a gradual diminution of the maximum value of the population that the limited environment will support. When combined, these factors suggest that the life cycle figure should in its earliest stages display unconstrained exponential growth of population when the population density is small and the ability of the environment to supply necessary resources and diffuse undesirable societal byproducts is correspondingly great, Thereafter, a period should follow wherein the geometrical constraints of the finiteness of the environment enforce an absolute limit on the supportable population. These two stages are exhibited in [link] , [link] , and [link] , and the cycle of United States population growth displays the first and the early effects of the second ( [link] ). A subsequent third stage follows, wherein the maximum supportable population declines gradually and steadily, ultimately to zero, so that the entire life cycle might appear somewhat as shown in [link] below.