Antislavery agitation spread through reformers with American contacts, but Britain’s movement to abolish the slave trade became the largest social movement of the era. Publishing damning exposés of the traffic, lobbying Members of Parliament, and forming vibrant locals across the British isles, the movement sponsored massive petition-signings that (unlike preceding reform movements) mobilized across social class, while women were also mobilized for boycotting against slave-produced products. The movement only failed to produce immediate results due to a countermovement centered in the slave ports that raised counterpetitions and lobbied for British economic self-interest, particularly once war against Revolutionary France began in 1793.

Historians, like contemporary activists, use numbers to make moral claims: the greater the number of victims, the greater the moral value of a given phenomenon. But rarely do historians or contemporary activists reflect on how they use numbers or historicize the complex ways numbers have clarified or conversely obscured ethical claims about stopping slavery. In “Counting Modern Slaves,” I examine the particular political work that counting slaves has historically accomplished. I begin with the first British actors to make counting slaves profitable, the metropolitan architects of the planet’s first global marketplace, one in raced slaves. I then consider how abolitionists on both sides of the Atlantic flipped that calculating script by brilliantly deploying metrics to hammer home key arguments about the universal values in slavery’s demise. Contemporary abolitionists, in turn, have eschewed the racism of the quantifying architects of the slave trade, but use numbers to aggregate modern slaves without clarifying the ethical choices that shape their calculations. In “Counting Modern Slaves,” I do not condemn using numbers, but rather seek to clarify how, when, and why counting slaves has accomplished its emancipatory possibility.

Quakers, originally from The Netherlands and Germany, were the first to formulate criticism of slavery in the Caribbean and North America in the Germant0own Declaration of 1688. Only in the late 18th century Quakers also had political influence in the UK, e.g. through the discourse of Wilberforce and Thomas Clarkson, describing the horrors of the Middle Passage. At the same time in France, some Enlightenment philosophers also critical of slavery, though often ambiguously. Most explicit was the discourse of Condorcet.