Epilogue: expanding the capital stock.

This article discusses sustainable development and the four types of capital: man-made capital natural capital human capital and social capital. Sustained progress requires preservation and expansion of the capital stock. Man-made capital is the primary focus of development: buildings factories machines and infrastructure. Natural capital includes natural resource assets such as minerals soil forests air water and wetlands. These goods are renewable or nonrenewable and marketable or nonmarketable. These assets have become increasingly scarce. Human capital includes investments in for instance education health and the nutrition of individuals. Human and social capital are difficult to quantify in terms of monetary value. Social capital is represented by the institutional and cultural bases of society. The authors refer to the thesis of Robert Putnam that civic community guarantees good governance and is key to sustained socioeconomic growth. Strong civic community means voluntary horizontal organizations and hierarchical vertical associations and their denseness in society. Putnam found that in Italy there was a preponderance of voluntary horizontal associations in the northern prosperous and rapidly developing parts of the country. Autocratic vertical institutions were found in the less effective parts of southern Italy. The evidence suggests that good government is nurtured by long-standing civic involvement. Capital stock is related to sustainable development to the degree to which researchers can measure each kind of capital define the production function define an exchange rate and define the threshold within which the more efficient activities can be selected. Sustainability can be weak sensible strong and very strong depending on the measure of nondeclining capital. The author recommends the progression in improvement of measurement rather than an interminable debate about the perfect formula.