In section 8.1, Keynes introduces the ‘propensity to consume’ as a functional relationship between a given level of income in terms of the wage-unit () and the amount of that income spent on consumption, also measured in terms of the wage-unit (), such that: Here, the level of actual consumption is distinct from , the expected level of consumption estimated by the entrepreneur, as part of the entrepreneur’s expected proceeds . In this sense, is an approximation or expectation of . He also argues that the propensity to consume can be adequately understood in terms of subjective factors and objective factors.