For reasons both of a peripatetic existence, of the places in which that has taken place, and a growing concern in the relationship between power and the capacity to make definitions, topographic and otherwise, I have been thinking about borders, and what Greek and Roman antiquity might contribute to such a contested concept.

1. The ubiquity of borders

Borders and boundaries have been ubiquitous.  We have seen the moment when the period since the fall of the Berlin Wall exceeded the time of its existence.  The most contentious remaining element of the current negotiations between the UK and Europe revolves around a border we thought we had almost eradicated.  Boundaries from picket lines to barbed wire lines to threatened walls have etched their cartographic existence into geographic memory, whilst metaphoric red lines and hostile environments have contributed to devastating psychological and physical damage.

A world without borders is barely conceivable in…