1 The people in the Blue table have the item and are willing to sell it for the price listed.
Definition. An ethical philosophy in which the happiness of the greatest number of people in the society is considered the greatest good. According to this philosophy, an action is morally right if its consequences lead to happiness (absence of pain), and wrong if it ends in unhappiness (pain).
1 PU doesn't say that we should promote the greatest good for the greatest number, although often that is the way to maximize the aggregate amount of happiness. Indeed, Bentham seems to have adopted the principle greatest good for the greatest number..  PU introduces a gradation of right and wrong actions.