Quoting ‘Economic Calculation: Postscript’ by Joseph T. Salerno

Mises thus assumes in all his writings on the subject that the planners have full knowledge of consumer valuations of final goods as well as of the various means available for producing these goods under known technological conditions. For example, Mises [pp. 23] writes, “The administration may know exactly what goods are most urgently needed…. It may also be able to calculate the value of any means of production by calculating the consequence of its withdrawal in relation to the satisfaction of needs.” Despite this knowledge, the socialist administrators would be unable to arrive at a useful social appraisement of the means of production in cardinal terms. This can only occur where there exists private ownership and exchange of productive resources, which generate catallactic competition among independent producers resulting in the imputation of meaningful money prices to the resources.

via Economic Calculation: Postscript.