's aim. For example, there are many medical experiments using people as object, surely enough without danger of life. Otherwise people should not be used, unless there is no other ways and it is able to save many lives. Generally, however, solutions are able to be found, like using animals to do medical experiments. Sacrifice of soldiers on the battle fields is the means to protect others.

There are up-up relations everywhere, which is accepted willingly and almost never arouse contradiction, and is the basis of cooperation and unification of benefit. In this case, benefit of each person is the criterion of justice and ought to be improved.

Theorem: Benefit of each person is the criterion of justice when benefits of people are in the up-up relation.

The up-down relation is able to be transformed into up-up, if people change the conditions in a proper way, to realize win-win and avoid struggle. For example, everyone obey the transportation rules and build some flyovers. The concrete ways to make win-win, therefore, should be sought and made as more as possible, which is also a kind of justice, a more important justice.

Theorem: The effort to seek and make concrete ways to realize win-win is justice.

The win-win is harmony, which is possible to reach the Pareto Optimality. Everyone is keen on wealth, and the best way is by up-up.

Love or benevolence is an important way to change the up-down to the up-up besides even bargain. Confucius and Jesus discovered the function of love, so they dedicated their lives to promote it.

The even bargain is also an important way to win-win. Adam Smith submitted, in An Inquiry into the Nature and Causes of Wealth of Nations, the principle of personal utility, invisible hand and even bargain. As a result, the British Premier at that time called him “teacher”.

Immanuel Kant was wrong to say that it has not genuine moral worth to help others from inclination.²⁹ In fact, this kind of action is one of the best ways to realize win-win, and should be advocated．Kant regard the good, not from inclination but from duty, as a moral worth and beyond all comparison the highest.