Justice is the central star which governs societies, the pole around which the political world revolves, the principle and the regulator of all transactions. Nothing takes place between men save in the name of right; nothing without the invocation of justice. Justice is not the work of the law: on the contrary, the law is only a declaration and application of justice in all circumstances where men are liable to come in contact. If, then, the idea that we form of justice and right were ill-defined, if it were imperfect or even false, it is clear that all our legislative applications would be wrong, our institutions vicious, our politics erroneous: consequently there would be disorder and social chaos.
This hypothesis of the perversion of justice in our minds, and, as a necessary result, in our acts, becomes a demonstrated fact when it is shown that the opinions of men have not borne a constant relation to the notion of justice and its applications; that at different periods they have undergone modifications: in a word, that there has been progress in ideas. Now, that is what history proves by the most overwhelming testimony.

Justice is the product of nature and labour

Justice is the application of previously decided and accepted norms of conduct and the rules for their examination and dispute. It is as imperfect as any other institution. But a dispassionate, considerate, supportable, and moral resolution of differences is the goal toward which it aspires.

Justice is primarily a possible, but not a necessary, quality of a social order regulating the mutual relations of men. Only secondarily it is a virtue of man, since a man is just, if his behavior conforms to the norms of a social order supposed to be just. But what does it really mean to say that a social order is just? It means that this order regulates the behavior of men in a way satisfactory to all men, that is to say, so that all men find their happiness in it. The longing for justice is men's eternal longing for happiness. It is happiness that men cannot find alone, as an isolated individual, and hence seeks in society. Justice is social happiness. It is happiness guaranteed by a social order.

Modern capitalism violates right order because it so employ the working of wage earning classes as to divert business and economic activity to its own advantage without any regard to the human dignity of the workers, the social character of economic life, social justice, and the common good.

Justice is the first virtue of social institutions, as truth is of systems of thought. A theory however elegant and economical must be rejected or revised if it is untrue; likewise laws and institutions no matter how efficient and well-arranged must be reformed or abolished if they are unjust. Each person possesses an inviolability founded on justice that even the welfare of society as a whole cannot override. For this reason justice denies that the loss of freedom for some is made right by a greater good shared by others. It does not allow that the sacrifices imposed on a few are outweighed by the larger sum of advantages enjoyed by many. Therefore in a just society the liberties of equal citizenship are taken as settled; the rights secured by justice are not subject to political bargaining or to the calculus of social interests.

We've heard many people say and have often said ourselves that justice is doing one's own work and not meddling with what isn't one's own ... Then, it turns out that this doing one's own work-provided that it comes to be in a certain way-is justice.

In capitalist society, under the conditions most favorable to its development, we have more or less complete democracy in the democratic republic. But this democracy is always restricted by the narrow framework of capitalist exploitation and consequently always remains, in reality, a democracy for the minority, only for the possessing classes, only for the rich. Freedom in capitalist society always remains about the same as it was in the ancient Greek republics: freedom for the slave owners

Justice is the constitution or fundamental law of the moral universe, the law of right, a rule of conduct for man in all his moral relations. Accordingly all human affairs must be subject to that as the law paramount; what is right agrees therewith and stands, what is wrong conflicts and falls. Private cohesions of self-love, of friendship, or of patriotism, must all be subordinate to this universal gravitation towards the eternal right.

Justice is moral temperance in the world of men. It keeps just relations between men; one man, however little, must not be sacrificed to another, however great, to a majority, or to all men. It holds the balance betwixt nation and nation, for a nation is but a larger man; betwixt a man and his family, tribe, nation, race; between mankind and God. It is the universal regulator which coordinates man with man, each with all, — me with the ten hundred millions of men, so that my absolute rights and theirs do not interfere, nor our ultimate interests ever clash, nor my eternal welfare prove antagonistic to the blessedness of all or any one. I am to do justice, and demand that of all, — a universal human debt, a universal human claim.

What the marchers on Washington knew, what the marchers in Selma knew, what folks like Julian Bond knew, what the marchers in this room still know, is that justice is not only the absence of oppression, it is the presence of opportunity. Justice is giving every child a shot at a great education no matter what zip code they’re born into. Justice is giving everyone willing to work hard the chance at a good job with good wages, no matter what their name is, what their skin color is, where they live. Justice is living up to the common creed that says, I am my brother’s keeper and my sister’s keeper. Justice is making sure every young person knows they are special and they are important and that their lives matter -- not because they heard it in a hashtag, but because of the love they feel every single day not just love from their parents, not just love from their neighborhood, but love from police, love from politicians. Love from somebody who lives on the other side of the country, but says, that young person is still important to me. That’s what justice is.

Justice is truth in action.

Secondly, what does justice require? In the end, it requires liberty.

...a theory of justice that can serve as the basis of practical reasoning must include ways of judging how to reduce injustice and advance justice, rather than aiming only at the characterization of perfectly just societies – an exercise that is such a dominant feature of many theories of justice in political philosophy today.