Methods of quantitative measurement are the foundation of scientific modernity; systems of classification are the basis of political power. Somewhere between the two lies truth. From prehistoric systems of sheep-counting to the mapping of the human genome, our sense of self and social order is yoked to an instinct to enumerate the world around us – to tally, to classify, to analyse, to understand (Nassir Ghaemi, 2009). It has been suggested that ‘[t] he only sound way to appraise the state of the world is to count’ (Pinker and Mack, 2014). To which estimably concise proposition, the only appropriate answer is, yes; but count what? How? For what purpose? And who decides?

Take people. Enumerating the size and composition of a population has been central to processes of state formation and the projection of government power from Han China to modern Europe. But while numbers may be gathered, their significance remains highly contested – from the fight for birth registration in marginal communities to the bitter struggles over census methodology – in countries from Afghanistan to America – disputing numerical superiority, geographical control, national identity and political power; or the contestation over population itself as societal necessity or existential species threat (Rosen, 1958; Glass and Eversley, 1965; Livi-Bacci, 1992; Kertzer et al, 2001; Todres, 2003; Lundberg et al, 2008; Carr-Hill, 2013; Visoka and Gjevori, 2013; Strmic-Pawl et al, 2018; McMichael and Weber, 2021).

The idea of truth is, in any case, something of a fallacy – the eternally imperfect reconciliation of perception and reality (Ramsey, 1927). From Plato to Nietzsche, via Heisenberg and Schrödinger, we encounter time and again fundamental limits in our ability to define the reality we inhabit, finding ourselves suspended probabilistically somewhere between accuracy and error (von Mises, 1957). It is, perversely, in the realm of concept that we are closest to capturing that reality. But as we convert concept into language, language into speech and speech into the endless nuance of human interaction, our ability to agree the truth of things – in particular what we owe one another as members of a common society – fragments (Wittgenstein, 1953; Levi-Strauss, 1955; Gard, 2011).