There are only two species of justice: distributive justice and rectificatory justice. Distributive justice is primarily concerned with the distribution of rights and duties to members of society by way of society's institutions. Included in this concern for a just distribution of rights and duties is a concern for those members of society who are disadvantaged in their opportunities to participate in the benefits of social cooperation. When such disadvantages arise, distributive compensation is due to these members of society as a means of removing the disadvantage. To compensate for something is to counterbalance it; to give something equivalent in value to the thing. “The root of ‘compensate’ is “to weigh,” that is to weigh different things together in order to establish a balance between them…‘compensation’ carries the connotation of providing something equivalent in value to that which has been lost.” In the case of distributive compensation, this rendering of an equivalent in value is done in order to alleviate some disadvantage or natural loss that is thought to pose an undue hindrance on members of society.