The resultant theory was challenged and refined several times in the decades following its original publication in 1971. A significant reappraisal was published in the 1985 essay "Justice as Fairness", and a subsequent books under the same title, within which Rawls further developed his two central principles for his discussion of justice. Together, they dictate that society should be structured so that the greatest possible amount of liberty is given to its members, limited only by the notion that the liberty of any one member shall not infringe upon that of any other member. Secondly, inequalities – either social or economic – are only to be allowed if the worst off will be better off than they might be under an equal distribution. Finally, if there is such a beneficial inequality, this inequality should not make it harder for those without resources to occupy positions of power – for instance, public office.