Robert Solow was a leading theorist of economic growth. In one of his two pioneering papers, he showed that, with labour fully employed, the long-run economic growth rate is independent of the saving rate. In the other, he argued that only a minority of economic growth can be explained by increases in labour and capital inputs; the residual (now called “the Solow residual”), which presumably reflects technological innovation, accounts for the majority. That same growth accounting suggests, among other things, that new capital is more valuable than old capital because it embodies more up-to-date technology. Solow also made major contributions on fiscal policy, wage bargaining, natural resources and other topics.