Rules and duties exist to correct for partiality. The point of justice is that it applies equally, even when love does not. A judge cannot acquit someone because she loves him, a doctor cannot favour a patient because he is charming. Love without principle too easily becomes nepotism or tribalism. The most brutal conflicts in history were driven by deep love for one’s own group, not lack of it.
Love matters for motivation. It can inspire people to act with kindness. But moral frameworks require more than sentiment. They need universality and consistency, which only rules and duties can provide. Murdoch’s vision mistakes a source of energy for the standard itself. Without shared norms, love does not scale beyond the private sphere.