With my fellow Brits voting collectively to leave the EU, these words written in 1624 come to mind:
No man is an island,
Entire of itself,
Every man is a piece of the continent,
A part of the main.
If a clod be washed away by the sea,
Europe is the less.
As well as if a promontory were.
As well as if a manor of thy friend’s
Or of thine own were:
Any man’s death diminishes me,
Because I am involved in mankind,
And therefore never send to know for whom the bell tolls;
It tolls for thee.
John Donne 1572–1631, poet, Dean of St Paul’s Cathedral, London, and member of Parliament.

John Donne, after a miniature by Isaac Oliver, possibly 1616.
© National Portrait Gallery, London - NPG 1849