If you've heard Hayek's name, it will have been as Keynes' arch enemy - the "Austrian" economist who wrote the Road to Serfdom and believed that markets should be as free as humanly possible.

BBC: Masters of money: John Maynard Keynes

On the undercard earlier on Saturday, Commonwealth super-middleweight champion George Groves got off the floor and stopped Scot Kenny Anderson to defend his title and move closer to a possible showdown with arch enemy James DeGale.

BBC: David Haye stops Audley Harrison to retain WBA title

For the time being, though, the divided left has elected a winner already: its arch-enemy Silvio Berlusconi.

ECONOMIST: The Italian left

Mr Torrijos junior's strongest challenger, Mireya Moscoso, is the widow of a former president, Arnulfo Arias, who was General Torrijos's arch-enemy.

ECONOMIST: Panama

Brahma, though stronger, lacks a premium-brand soft drink, which its former arch-enemy has in the form of Guarana Antarctica, a type of fruit soda.

ECONOMIST: Mergers in Brazil

Mr Duhalde retains control over this political machine, which he deployed to help Mr Kirchner defeat his arch-enemy Carlos Menem, Argentina's president from 1989-99.

ECONOMIST: The president seeks allies, far and wide

What is odd is that the new boss, Piotr Farfal, comes from the League of Polish Families (LPR), a radical right-wing outfit, normally seen as an arch-enemy by Warsaw's liberals.

ECONOMIST: Poland's public television

Despite Rubio's rise, he is largely a darling of the Tea Party, and its supporters have been the arch-enemy of the left as they are driving GOP candidates further to the right.

CNN: Florida race could haunt Democrats in 2012

They are often accused of working for Saad Hariri, Lebanon's former prime minister, once again an arch-enemy of Mr Assad, or for Prince Bandar bin Sultan, a Saudi who heads his country's national security council.

ECONOMIST: The crisis in Syria: More stick than carrot | The