Commentary Par XVIII 91

It is not surprising that justice, most blatantly evident as a guiding concern for this poet in this canto (where it is literally spelled out in capital letters), has caught the attention of nearly all who deal with it.  Giglio's lectura (Gigl.1988.1) is little more than a meditation on Dante's conception of justice.  And see Chimenz (Chim.1956.1), p. 1735, supporting a definition of the Commedia as a 'poem of justice, both human and divine.'  In this vein, see also Scott (Scot.1996.1), p. 55, citing Dante's epistle (Epist.XII.7), where he refers to himself as a 'preacher of justice' (vir predicans iustitiam).  For consideration of Dante's sonnet 'Se vedi gli occhi miei' as underlining his continuing concern for justice and as perhaps influencing Ambrogio Lorenzetti's allegory of Injustice (in the Palazzo Pubblico of Siena), see Giunta (Giun.2005.1).

For a consideration of the centrality of justice to Cantos XVIII-XX and to the poem as a whole, see Took (Took.1997.1).  Scartazzini (DDP Scartazzini.Par.XVIII.70-99) refers to two earlier passages that reveal Dante's overwhelming respect for this ideal: 'Thus, although every virtue in man is deserving of love, that is most deserving of love in him which is most human, and that is justice' (Conv.I.xii.9 -- tr. R. Lansing); '... Justice, which disposes us to love and conduct ourselves with rectitude in all things' (Conv.IV.xvii.6 – tr. R. Lansing).