Law of equi marginal utility

Definition: prof. Alfred Marshall has stated the law as follows- a person has a thing which can be put to several uses he will distribute it between these uses in such a way that it has the same marginal utility in all.

Explanation: In other Words he will substitutes a commodity of greater utility for a commodity of lesser utility . a person derives maximum satisfaction, when the marginal utilities of all the commodities purchased by him are equalised. that is why the principle is also known as 'Doctrine of Maximum Satisfaction.