The term social justice is a relatively recent addition to human thought, emerging in the 1840s, meaning that individuals should be accorded equal access to opportunities and privileges within a society. Social justice holds that everyone deserves equal rights. In Europe, the term came into widespread use around the 1848 revolutions, when the idea of capitalism was destroying lives led to fundamental shifts in thinking. In America, the term became used during the Progressive era, when many of the same ills of unrestrained capitalism began to become obvious among the lower classes of society.
Many international organizations work towards the establishment of social justice in the world, predicated on the ideas that peace, democracy, and human rights are essential to human dignity. One of the largest institutions to speak out on the need for social justice has been the Catholic Church. One of the foundations of that religion is its concern for the poorest and most vulnerable members of society. In 1891, Pope Leo XIII published an encyclical, Rerum novarum (On the Condition of the Working Classes), which was one of the earliest statements regarding class conflict in the world.
In philosophy, thinker John Rawls is highly associated with social justice. His work A Theory of Justice discusses the problem of distributive justice and the social contract, declaring that every person is entitled to an equal right to liberty and that social justice should be geared towards the benefit of the least advantaged in society.