ABSTRACT
In the foregoing account of the consumer's behavior, the "income" considered was his current income, i.e., the income that accrues during the same period in which his consumption spending is done. Just as a demand curve shows what quantity of a commodity will be demanded at each possible price, so the consumption function shows what expenditure consumers will wish to make on consumers' goods and services at each possible level of income. To justify the use of the consumption function, therefore, it is important to produce evidence to show that income is, if not the sole determinant of consumers' demand, at least the most important of the many factors that can be held to influence it. Even so, they are particularly instructive in showing possible ways in which consumers' decisions may be affected by expectations as well as by current income, and they have provided a useful stimulus to research on the nature of the consumption function.
