Among the many sets of interests that we all have are class interests. For Green the common good is realised when all can realise their own goods. Marx says something similar when he says that he seeks a society where the full development of all is the pre-condition of the full development of each . The Blairite vision, at its rhetorical heights, has something of this tenor. Blairite One Nationists, for all their talk of social exclusion, deny that class division, and exploitation, is endemic to capitalist society.
Socialists say that it is.
Clearly the Roussean vision is deeply conservative, backward looking and suffocatingly conformist. Rather, Marx, tells us we need to move forward to a classless society. The message of socialists to other progressives is that the realisation of the common good requires common ownership. And against the class interests of those who seek to reduce the world to nothing but a means to more and more profits.