Hayek's work on the microeconomics of the choice theoretics of investment, non-permanent goods, potential permanent resources, and economically-adapted permanent resources mark a central dividing point between his work in areas of macroeconomics and that of almost all other economists. Hayek's work on the macroeconomic subjects of central planning, trade cycle theory, the division of knowledge, and entrepreneurial adaptation especially, differ greatly from the opinions of macroeconomic "Marshallian" economists in the tradition of John Maynard Keynes and the microeconomic "Walrasian" economists in the tradition of Abba Lerner.