A Review of the Population Sector in The Limits to Growth

Abstract

A technical exposition and review is presented of the demographic sector of the computer model that was the basis of the book The Limits to Growth by Donella H. Meadows et al. The model summarizes in the form of over a hundred mathematical equations the basic causal relationships between the major variables believed to be 1) the determinents of growing industrialization 2) rapid population growth 3) widespread malnutrition 4) depletion of nonrenewable resources and 5) increasing environmental pollution. The author states that the significance of the present model probably lies not in the projections it makes but in the fact that it is the first attempt to construct a complete population model. All variables and causal relationships that the Meadows team considered important as determinants of population change are allowed to interact simultaneously in 1 model. The author makes certain recommendations. He suggests that the model would be more realistic if there was disaggregation to a regional or subregional level where population behavior is more homogeneous. The testing of the model should be extended possibly in smaller populations where extensive reliable data are available. An effort should be made to specify certain of the quantitative relationships especially the sensitive ones in more detail and with more data. The model would probably benefit from an expansion into subsubmodels in a number of places depending on what it is used for. The population model is recognized as a new and challenging attempt to come to grips with the complex dynamic and nonlinear nature of demographic processes but much work remains to be done if it is to be used for anything other than crude global population projections.