2. Aggregation across consumers Can a society behave like a ration man? If a society behave like a ration man, can the utility of this"man represented the welfare of society? Aggregate demand: x(p…m)=∑x(P) Wealth distribution w=(w,wn) And total wealth w=∑2.Aggregation across consumers • Can a society behave like a ration man? • If a society behave like a ration man, can the utility of this “man” represented the welfare of society? • Aggregate demand: • Wealth distribution • And total wealth 1 1 ( , ) ( , ) I I i i i w w x w = x p p =  1 ( ) w = w wI 1 I i i w w = = 