"Professor Mises' denial of the possibility of economic calculation in a socialist system must be rejected. However, Professor Mises' argument has been taken up recently in a more refined form by Professor Hayek and Professor Robbins. They do not deny the theoretical possibility of a rational allocation of resources in a socialist economy, they only doubt the possibility of a satisfactory practical solution of the problem. […] The position taken by Professor Hayek and by Professor Robbins is a significant step forward in the discussion of the problem. It promises a much more fruitful approach than Professor Mises' wholesale denial of the possibility of economic accounting under socialism."