ON THE walls of George Osborne's office in 11 Downing Street are portraits of William Gladstone and Benjamin Disraeli, warring titans of 19th-century British politics. The chancellor of the exchequer chose his artwork long before Ed Balls became his opposite number on January 20th, after the resignation of Alan Johnson, the previous Labour shadow chancellor. The selection now looks prescient.

The rivalry between Mr Osborne (above left) and Mr Balls (right) is likely to be the story of this parliament. Their personalities, as well as their different perspectives on the economy, will see to that. Both men have a taste for the martial side of politics. Both are tribal members of their parties who shone as backroom advisers: Mr Balls to Gordon Brown when he was chancellor, Mr Osborne to various Conservative leaders. Voters have yet to warm to either, but both, in private, are laddishly garrulous and boast extensive hinterlands (Mr Balls is football-mad; Mr Osborne's rock-music collection reputedly stunned even Eric Clapton).

Mr Balls has long spoken of the dangers to a fragile economy of hasty spending cuts, and this week's alarming GDP figures lend some weight to his warnings. The ferocity with which he set about Michael Gove, his opposite number during his time as shadow education secretary last summer, has entered Brownite folklore. And then there is his sheer brainpower. Perhaps no serving British politician is better equipped for the painstaking work of building an economic policy than this economist and former Financial Times journalist, who has worked in the Treasury as both an adviser and a minister. He might never be lovable, but his earthy, plain-speaking style and faint regional accent could play better with financially squeezed voters than the conspicuously posh and metropolitan chancellor.

Still, the Tories believe he is a containable threat. Mr Balls—like Ed Miliband, the Labour leader—is tainted by association with Mr Brown, a hugely unpopular prime minister whose record as chancellor has also collapsed in popular esteem. Nor, say some, is Mr Balls really so very scary. In retrospect, it was the publication of mistaken information about school-building programmes that embarrassed Mr Gove, not the brilliance of his opponent. Despite considerable hype, Mr Balls failed to do much damage during his brief stint as shadow home secretary.

Both he and Mr Osborne aspire to lead their party and country; but this is potentially more disruptive for Labour than for the Tories. True, Mr Osborne has accrued influence far beyond his economic brief. He dominates the government's political as well as policy meetings, and is regarded by some as the unofficial chief executive of the coalition. But he has much better relations with David Cameron than Mr Balls has with Mr Miliband, whom he grew used to regarding as his junior in the Brown camp. Mr Balls has a following among Labour MPs, as his creditable third-place finish in last year's leadership election showed. Even if he behaves himself, he could still overshadow his boss through sheer talent and energy.

Mr Balls has a strongly held world view: he is a social democrat. He has a faith in the state that is typical of his party's Fabian wing, minus the cultural liberalism that usually comes with that label. Mr Osborne has beliefs too—in free markets, in balanced budgets, in an assertive foreign policy—but he is ultimately concerned with winning.

The difference is born of very different experiences in politics. Mr Osborne has never known personal adversity, but he has suffered plenty of the political kind. He toiled in the backrooms of the crumbling John Major government. He worked for the agriculture secretary during the mad-cow crisis. He was an aide to William Hague, now the foreign secretary, when Mr Hague floundered as Tory leader.

These traumas left him with a remorseless focus on achieving power for his party. He was convinced of the need for the Tories to rebrand themselves as modern and compassionate long before Mr Cameron was. Mr Balls, who did not experience Labour's comparably crushing defeats in the 1980s at first hand, is less wary of fixed beliefs and ideologies.

These are very similar and very different men. Their duel, while not quite worthy of the Victorian giants, is already compelling. Ultimately, though, it may be the economic cycle that decides the winner.