Not from Benevolence
Our duty to look after our own interests is right and proper.
[each individual] stands at all times in the need of the co-operation and assistance of great multitudes, while his whole life is scarce sufficient to gain the friendship of a few persons...
...It is not from the benevolence of the butcher, the brewer, or the baker, that we expect our dinner, but from their regard to their interest.
Adam Smith
We can all dream of a world in which everyone puts aside their own selfish interests and seeks the good of all. But this is not just unattractive it is undesirable. Our duty to look after our own interests is right and proper. It is the only way in which our own needs can be met in a way which is both coherent and respectful.
Other people can never look out for our own interests with the necessary eye for detail. It is hard enough doing it as a parent for a child we love, it is impossible to do it as a collective on behalf of everyone. Only we know ourselves from the inside out.
More remarkably still, as Smith observes, if kept within certain bounds, this kind of proper self love is of great benefit to everyone. Our own need for the things that only other people can provide creates a healthy interdependency. Nature makes sure that we need other people and that they need us.
The great danger however is that looking after our own interests can be turned into an idol or a god. Love for the self will not solve every problem. It will not protect the world itself nor will it protect the interests of those who are endangered by others.
We also need to love other people and we need the discipline to ensure that we can find the right balance between these two loves. It is for this reason that society develops rules and institutions that help us keep these loves in balance. The search for social justice is the search to find the right balance between love for self and love for others and the world we share.
However even social justice can be corrupted. When we begin to see some people as just too different we can be tempted to separate them from the interconnecting web of human need. Then we are in danger of making the most fatal mistakes. The eugenicist, the racist and the meritocrat all share the same mission to redefine humanity so that they only have to focus their love for others on some smaller group - some group within which they find it easier to see a mirror image of themselves.
True social justice will always be inclusive, will always seek to define itself primarily by its concern for those who are most likely to slip out of consideration all together.