we need far more empirical study than we have had so far of the universe of inventors; any finding concerning inventors... would be of great value...… - Simon Kuznets

[The principal characteristic of this economic epoch is] a sustained increase in per capita or per worker product, most often accompanied by an increase in population and usually sweeping structural changes.

Distinctions must be kept in mind between quantity and quality of growth, between its costs and return, and between the short and the long term. Goals for more growth should specify more growth of what and for what.

The inescapable conclusion is that the direct contribution of man-hours and capital accumulation would hardly account for more than a tenth of the rate of growth in per capita product — and probably less. The large remainder must be assigned to an increase in efficiency in the productive resources, or the effects of changing arrangements, or to the impact of technological change, or to all three