ABSTRACT
As a first-order condition for a maximum: the marginal utility of a unit of income, whose price by definition is unity, equals the marginal utility of a dollar's worth of leisure, or (with opposite sign) the marginal disutility of a dollar's worth of a supplied. The purist will note that, while income y0 from sources other than a might have been added explicitly to the Lagrangian equation, making its second term
- λ [α pa - (y-y0) ],
our result (9.2) would have remained the same.
