What does a king do when his privileged but dysfunctional son turns against him, flees to America and spends his time there attacking the monarch and his family? King Charles’s reaction has been to let him get on with it. But given what he might have done, the Stoic philosopher Seneca (d. ad 65), and adviser to Nero would have seen this as an admirable act of mercy.

In his essay on that subject (De Clementia), Seneca discussed the case of Tarius, who discovered that his son was plotting to murder him. In such circumstances, it was customary for the father, who had the right of life and death over his whole household, to summon a private council of family and friends, which in this case included the emperor Augustus, to decide what action to take. If the death penalty was agreed, the traditional punishment for a parricide was to be flogged, sewn up in a sack together with a cockerel, a snake, a monkey and a dog – good luck with that – and thrown into the sea.

The case was heard, and the evidence of the son and the contents of the accusation examined and discussed. Augustus then ordered each man to write down his own judgment in a secret vote, to prevent them all from simply agreeing with the emperor. They concluded that the son should be banished to whatever place seemed best to his father. After all, the son had been too timid to commit the deed, effectively making him innocent and justifying a mild punishment. So the son was exiled to Marseilles (a wealthy, cultured place, very popular with Roman exiles) with the same allowance that he was already receiving.

Seneca applauded this decision, with which Augustus was in full accord. As the philosopher wrote, the wise man will look not to the past but to the future, to improve the wrongdoer, like the good farmer who tends trees that stand tall, but applies props to those that have grown crooked, trims the overgrown, fertilises those in poor soil, and so on. Perhaps His Majesty is putting his faith in his son to grow up, in the hope that all can be forgiven?