 So far we have been discussing Kagan’s theory of non-comparative desert. His theory of comparative desert is meant to answer questions like the following: suppose that there are two people, that one of them is getting more welfare than he deserves, and that there is nothing we can do about that. What must the welfare level of the other person be, if the demands of comparative desert are to be perfectly satisfied? Kagan advocates what he calls the “Y-gap” view. The image below illustrates this view. Suppose that the mountain on the left represents the person whose welfare level we cannot control, and the mountain on the right represents the person whose welfare level we can control. Then we should overcompensate the person on the right by that amount which results in his Y-gap being the same as that of the person on the left. A person’s Y-gap is the vertical distance between the peak of his mountain, and his actual location (in this case) on the eastern slope. The vertical bars in the diagram depict the two Y-gaps. In this case, although the person on the left is over-compensated by amount A, the person on the right must be over-compensated by a greater amount B, to achieve the same Y-gap, and so to perfectly satisfy the demands of comparative desert, as Kagan sees them. 