Since the development of the Solow Growth Model by Robert Solow, it has been argued by many that capital is not the real source of economic expansion, but that technology is. This is so, it is argued, because capital, like labor, faces diminishing returns, so that as we increase capital investment, at some point total output reaches a maximum and then economic expansion resulting from increased capital will be exhausted. The source of sustained economic progress, therefore, must be technology, according to this view.
What are we to make of this argument? It is certainly true that new and better technology allows for more efficient production. As I note in my book, Foundations of Economics, according the the USDA, in 1987 it took the average American farmer 3 hours to produce 100 bushels of wheat, compared to 275 hours it took the average American farmer to do the same thing in 1830. Since the 1830’s there has been tremendous technological advance in the number and quality of tools, equipment, fertilizers, and pesticides available for farmers, greatly increasing farmer yields.
Is technology, then, a separate component generating economic expansion? As the knowledge regarding how to do something, technology does set a limit on our production. As Rothbard notes in Man, Economy, and State, however, capital is a narrower limit. For technology to be usable it must be bound up in actual capital goods. It does no good for a secretary to know that he could use an electronic device to type and edit written documents if programmed correctly, if he does not have access to an actual personal computer. In order to take advantage of technology, we must, consequently, have capital investment. Rothbard summarizes,
Therefore, it turns out that capital is the relevant factor for economic expansion. Without capital investment, technology is of no use. With capital investment, technology will advance as entrepreneurs continually seek to use better, more efficient, capital goods.
To expand production, the important consideration is not so much technological improvement as greater capital investment. At no time has invested capital exhausted the best technological opportunities available. Many firms still use old, unimproved processes and techniques simply because they do not have the capital to invest in new ones. They would know how to improve their plant if capital were available. Thus, while the state of technology is ultimately a very important consideration, at no given time does it play a direct role, since the narrower limit on production is always the supply of capital (p. 626).