If justice is the rock on which political civilisations are founded, its currency in public discourse seems oddly volatile (Greenberg and Cohen, 1982). Vernacular interest in justice throughout modern Europe peaks in the first half of the 19th century as revolutionary democratisation, economic industrialisation and evolutionary science engendered new concepts of biological individualism and social causation, merging natural and moral orders with more material questions of capital and labour, productivity and wealth.1 But its salience wanes over the following century – perhaps under the pressure of early globalisation, as soaring inequality through the Belle Époque and the Gilded Age gives way to economic nationalism and the onset of two world wars (Figure 8.1).

That trajectory, particularly in ideas of ‘social justice’, starts to reverse between 1900 and 1950 – likely fuelled by revolutions in Russia and China and the ‘great levelling’ of wealth and welfare in industrialised countries following the Second World War; rising faster from the 1960s, as struggles for colonial liberation and escalating opposition to racial injustice in the US combined with feminist, gay and Indigenous rights movements – all in the larger context of socialist and market economic ideologies competing, in cold conflict, for the offer of a better way (Figure 8.2).

The question of ‘global justice’ emerges more recently, rising sharply in the last 20 years, driven by growing concern for issues whose transnational nature is increasingly hard for states to sidestep, including a new wave of economic globalisation, resource exploitation and trade and the persistent challenges of poverty – all progressively overshadowed by the question of human survival as climate crisis and environmental damage provoke ever fiercer wars of words over science, truth, political liability and the fair distribution of responsibility (Figure 8.3) (Della Porta et al, 2007; Guo et al, 2019).

We know injustice when we see it (Figure 8.4) (Nagel, 2005). Yet our ability to define and agree what it requires, let alone to convert that into reality, seems trapped in a state of permanently incomplete philosophical gestation – rich in concept and contest but poor in concrete practice.