 “Practicalities” also shape human rights in Griffin’s view. He describes practicalities as “a second ground” of human rights. They prescribe making the boundaries of rights clear by avoiding “too many complicated bends,” enlarging rights a little to give them safety margins, and consulting facts about human nature and the nature of society. Accordingly, the justifying generic function that Griffin assigns to human rights is protecting normative agency while taking account of practicalities.