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Hello, the importance of oaths in the classical world can't be overstated.

Kings, citizens, soldiers, litigants, all swore oaths inviting divine retribution if they proved false to their word.

Oath cemented peace treaties, they oblige the Athenian citizenry to protect their democracy,

they guaranteed the loyalty of the Roman army to its emperor, they underpinned the legal systems of Athens and Rome.

And in Homer's epic poem, The Iliad, it's a broken oath to settle the dispute between Menelaire's and Paris that leaves the Greeks to storm Troy in pursuit of Helen.

But how did the classical world come to understand the oath?

Why did oaths come to occupy such a central place in the political, social and legal life of the Athenian state and what role did oath-making play in the expanding Roman Empire.

With me to discuss the oath is Mary Beard, Professor in Classics at the University of Cambridge, Alan Summerstein, Professor of

Greek at the University of Nottingham, and Paul Cartilage, Professor of Greek History at the

University of Cambridge.

Alan Summerstein, you say that an oath can best be understood as a conditional self-curse.

Could you develop that?

Yes, it's a note, really if you pick it apart, consists of three things. Firstly there's a declaration you're

asserting that something is the case or that you're telling the truth or you're promising to do something in the future.

And in the trade they talk about assertory oaths and promissory oaths.

Secondly, you specify the superior powers whom you're invoking as witnesses to punish you if the oath is false.

Normally, gods, but sometimes you'll be swearing by or on sacred or cherished objects.

And thirdly, you specify the curse that you're calling down on yourself if the oath is violated though often

that's left to be understood. Can you tell us when the idea of an oath heaved up

into ancient history? You mentioned now then the oath which is taken in the Iliad

...