John Rawls, who has taught at Harvard University from 1962 until his retirement sometime after 1993, was best known for A Theory of Justice. In that book, Rawls defended a theory of justice that sought to strike a compromise between the democratic ideals of equality and liberty. The theory was in the social contract tradition associated with John Locke and Jean-Jacques Rousseau, but Rawls introduced the idea that the contract would establish abstract principles of justice rather than specific laws or arrangements. Rawls’s contract was a hypothetical one involving agents who have been idealized in certain ways to create what he called an “original position.”
Rawls argued that the agents in this original position should be ignorant of their own abilities and prospects in order to ensure that the principles they choose will be fair ones. The result, he argued, would be egalitarian principles that would maximize the position of the worst-off persons rather than maximize overall utility and that would protect certain basic liberties. Rawls was also known for the idea that any theory should be judged on the basis of whether it is the result of a process of “reflective equilibrium” in which one considers competing theories and their implications, testing these against one’s intuitions about general principles and cases.