In all the talk in the Principles (as opposed to the formal analysis) it is not the saving of rentiers but the energy of entrepreneurs which governs accumulation.

economics limps along with one foot in untested hypotheses and the other in untestable slogans.

The point of studying economics is so as not to be fooled by economists.

Rosa Luxemburg maintained that the capitalist system can keep up its rate of investment (and therefore its profits) only so long as it is expanding geographically.

Not only subjective poverty is never overcome by growth, but absolute poverty is increased by it. ... Absolute misery grows while wealth increases.

Marx, however imperfectly he worked out the details, set himself the task of discovering the law of motion of capitalism, and if there is any hope of progress in economics at all, it must be in using academic methods to solve the problems posed by Marx.

It is a popular error that bureaucracy is less flexible than private enterprise. It may be so in detail, but when large scale adaptations have to be made, central control is far more flexible. It may take two months to get an answer to a letter from a government department, but it takes twenty years for an industry under private enterprise to readjust itself to a fall in demand.