As defined by Max Weber in his account of the market and bureaucracy, this refers to the extent of impersonal quantitative calculation (that is, risk assessment) that is possible and applied. Money is the best means for ensuring such calculability within a particular institutional order. The concept is best understood in contradistinction to (as well as in the context of) ‘substantive rationality’, which involves acting in relation to some ultimate values, be they status, egalitarian, social justice, or indeed any infinite variety of value-scales by which to judge the outcome of actions. Given certain substantive conditions—such as legal formalism, separation of employees from the means of production and administration, free labour, and a system of property rights—formal rationality refers to the calculability of means and procedures, substantive rationality to the value of ends or outcomes. The two are in constant tension, in so far as social action is oriented to ends, beliefs, and value commitment.