Throughout the English revolution of the mid-seventeenth century, churchmen disagreed about whom to exclude from taking holy communion, who should do the excluding, and how this exclusion should be imposed. The constant reclassifications of potential contaminants of church ritual fluctuated in tandem with larger socio-political processes. The ferocity of the debate in the 1650s reflects that decade’s social revolutionary chaos. Near the end of it, the label ‘idiot’ – whatever that may mean – arrives on the list, emerging from a dialectic of disputes which acknowledge the socio-political context. In that particular deployment of the label we start to see an outline of the modern psychological definition.