Main points of Robbins's defination of Economics

1 Unlimited Wants
Human wants are unlimited those wants can't be fulfill after fulfilled one another will appear there fore it is unpossible to satisfy all the wants.

2 Limited Means(resources)
Means available for satisfying those wants are limited or scarce since the man is not able to satisfy his unlimited wants with the limited resources.

3Alternative Use
All the wants can't be fulfilled by limited avialable means,some wants are more important and some are less and the resources are limited so that we have to fulfill our wants alternatively.

4 Wants Deffer in Urgency
all the wants are not equally important some wants are more urgency then other one, more urgency are satisfy firsr postponing the less urgency wants for a later date.for example medicine is more urgency then the cosmetic for girl.
5 Problem of choice
when the human wants are unlimited and the scarce means(resource)have alternative uses as well as wants differ in urgency.one has to make a choice as to when a particular wants should be satisfied .choice helps to derive maxmium satisfaction.

Comparison between Marshall's and Robbins's defiation of Economics

Marshall and Robbins have defined Economics in different ways but there are some similarities and differences between there definition which are mention below

Similarities

1 Study of human activities
Both Marshall and Robbins have given the primary place to human beings,both have ignored important of wealth and stressed in the human activities.

2 Wealth and scarce means
There is no fundamental difference between wealth and scarce means.Robbins used the words scarce means and Marshall used the word wealth which signify the same meaning because in economics wealth includes only those items that are limited all scarce to fulfill the unlimited desires.

3 Maximum welfare and Maximum Satisfaction
Marshall's definition reverse to the utilization of wealth for the promotion of maximum welfare and Robbin's definition referred to the utilization of scarce means for the maximum satisfaction therefore both their definitions signify the same meaning.

4 Human Behaviors
Marshall's definition has studies the human social behavior whereas Robbin's definition definition has studies all types of human behavior therefore both definitions has studied the human behavior.