What is seven times eight, Mr Osborne? When the cleverest response is to say nothing

Above all, the Chancellor has learnt from other people's mistakes

Osborne meets Sam Raddings (Getty)

George Osborne's refusal to answer the question "What is seven times eight?" shows how clever he is. He was being interviewed by a group of children on television when Sam Raddings asked if he was good at maths. He replied that he had taken maths at A-level, which I had forgotten, although it is in Janan Ganesh's excellent biography of him (he got straight As in maths, history and politics). Raddings then asked his follow-up question with the ruthlessness of a junior Andrew Neil.

"I've made it a rule in life not to answer a load of maths questions," said the Chancellor. An answer that will be deployed by many pupils taking a maths test in the next few days. But it is actually the right answer. Asking questions to try to catch a politician out is an old media game, and if children ask the questions it doesn't make it any better.

Osborne knows, because he is a politics obsessive, that Stephen Byers, when he was schools minister, was asked the same question and gave the wrong answer, saying 54 rather than 56. Byers is only human. Seven times eight is one of the harder questions in the times table, along with 12x8, 8x12 and 12x11 – the order makes a difference, apparently – but not as hard as 6x8 or 8x6, which one study identified as the most likely to trip people up. But it looked bad, just as it didn't look good that Byers, who was later transport secretary, could not drive.

Osborne might not remember, because it is irrelevant to his calculation, that Gordon Brown, when he was chancellor, was once asked, "What's 13 squared?" He repeated the question to buy time, but said "169" without further hesitation. I was impressed, but I doubt if anyone else was.

And that is the point. No one cares if you get the answer right. It is a story only if you get it wrong and, crucially, more of a story than if you rather obviously dodge the question. Osborne probably knew well enough that the answer was 56, but there is always a risk when you "know" the answer that a synapse has got crossed in the intraparietal sulcus and you will do a Byers on live television.

Which is a long way of saying that Osborne is good at politics. That should be obvious. You don't get to be Chancellor of the Exchequer by being useless. But there has always been something slightly surprising about Osborne's success. He is a poor public speaker, and has always had about him the air of someone who sees politics as a game. Yet here he is, in the second most powerful job in British politics (sorry, Nick Clegg), and often the subject of gossip among MPs on both sides about his leadership ambitions.

His great strength, which Ganesh brings out well in his biography, is that he regards politics as a craft. He does not share the fashionable view that politics is poorly served by the preponderance of former special advisers who have limited experience of so-called real life. As a former special adviser, he thinks that knowing about politics is an advantage. Above all, as the times tables affair shows, he has learnt from other people's mistakes.

The recent history of chancellors and prime ministers has often been unhappy, and David Cameron's view is that "the system is almost set up to cause conflict". This is true at the simple level, which is that a prime minister tends to want to spend public money while the Treasury's job is to stop it being spent. More fundamentally, economic policy lies at the heart of politics and differences are bound to develop over time. More serious still, the power of the chancellor means that leadership ambitions are almost bound to come into play.

Yet Osborne has learnt from Gordon Brown that the better way to become prime minister is to work with the incumbent. Brown would probably have succeeded earlier if he had at least pretended to support Blair. Likewise, Osborne's best chance is if Cameron wins next year and the two of them continue to work together. If Ed Miliband wins, the Conservative Party would be thrown into a leadership contest which Boris Johnson would be best placed to win. I am told that Cameron and Osborne expect Johnson to return to the Commons at or before the election. Osborne and Theresa May would be competing for the support of MPs to make the shortlist of two, from which party members would choose the new leader. Osborne has a better organisation among Tory MPs and candidates, but he would not have an obvious vote-winning pitch if the economy had just failed to deliver election victory.

Winning the election next year, on the other hand, would give him joint credit with Cameron and put him in a strong position to face the unforeseeable events of a second Tory-led government. Osborne knows the right answer to "What is seven times eight?" And he also knows the answer to "What lesson can you learn from the last chancellor to make it to No 10?"

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