Full Idea
Rawls saw four difficulties for justice in the social contract approach: future generations; justice across national boundaries; fair treatment of people with disabilities; and moral issues involving non-human animals.
Gist of Idea
The social contract has problems with future generations, national boundaries, disabilities and animals
Source
report of John Rawls (A Theory of Justice [1972]) by Martha Nussbaum - Creating Capabilities 4
Book Reference
Nussbaum,Martha C.: 'Creating Capabilities' [Belknap Harvard 2013], p.85
A Reaction
These are all classic examples of groups who do not have sufficient power to negotiate contracts.