science progresses by trial and error, and when it is forbidden to admit error there can be no progress.

The very nature of economics is rooted in nationalism. ... It [was] developed ... in the hope of throwing light upon questions of policy. But policy means nothing unless there is an authority to carry it out, and authorities are national.

Capitalism with near-full employment was an impressive spectacle. But a growth in wealth is not at all the same thing as reducing poverty. A universal paean was raised in praise of growth. Growth was going to solve all problems. No need to bother about poverty. Growth will lift up the bottom and poverty will disappear without any need to pay attention to it. The economists, who should have known better, fell in with the same cry.

It's a terrible thing to be a worker exploited in the capitalist system. The only worse thing is to be a worker unable to find anyone to exploit you.

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.

An economy may be in equilibrium from a short-period point of view and yet contain within itself incompatibilities that are soon going to knock it out of equilibrium.

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