Metric or imperial? It's a simple question. Yet even now, decades after Britain adopted the metric system, it still arouses extraordinary passions.
On the one hand, you have the old-fashioned romantics, who venerate tradition, eccentricity and national distinctiveness, and who still swear by feet, inches, acres and pints.
And on the other you have the metric rationalists, for whom the system of metres, centimetres, hectares and litres represents modernity itself.
All my life, the struggle has raged. With schools, retailers and manufacturers in the lead, Britain has largely been converted to the metric system.
Yet most of us remain attached to pints and miles, and even those brought up with the metric system still think in feet and inches. We talk of a strapping six-footer, not a 182 cm-er. We give someone an inch, and they take a mile — not 1.6 km.
Near Oxford University science buildings, the 25-year-old Roger Bannister (pictured) achieved what had once been thought impossible - running the world's first sub-four-minute mile
But is the imperial system seriously a product of the British Empire? That's the implication of a proposal by academics at Oxford, where as part of the university's 'decolonisation' project the maths, physics and life sciences faculty is suggesting students investigate the links between feet and inches and 'the idea of the Empire and Imperial standardisation'.
When I read those words, I had to stop and check they weren't a parody. Can any Oxford don genuinely think the imperial system is something to do with pith-helmeted imperialism?
Isn't it obvious that miles, yards, feet and inches date back centuries before Britain even acquired a single colony?
The great irony, in fact, is that it's the metric system which dates from the age of empires after the French Revolution, which is why it spread almost worldwide.
In its most familiar form, the imperial system dates from 1824, when Parliament passed the Weights and Measures Act to standardise units across the United Kingdom and its overseas possessions. Hence the 'imperial' nickname.
But all of these units had a longer history. Indeed, in many ways their history is that of our islands themselves.
Take the mile. It's certainly tied to the idea of empire. Not British, though — Roman.
A proposal by Oxford academics implies the imperial system is a product of the British Empire, but the mile is tied to the Roman Empire (above: Roman soldier), rather than the British
The word comes from the Latin mille passus, meaning a 'thousand paces'. The story goes that when Rome's legions marched through new territory, they planted a stick every thousand steps to help their military surveyors and road-builders.
Over time — and thanks to the difficulty of making precise measurements — the mile mutated. In almost every country it took a different form.
Thus, confusingly, an old English mile was about 1.3 modern miles, a Scottish mile was about 1.1 miles, an Irish mile was 1.25 miles and a Welsh mile was more than three modern miles.
Other ancient measurements were similarly convoluted. The acre, for example, derives from the Anglo-Saxon word aecer, which means an open field. But what was it, exactly? Well, Edward I's Statute Of Ells And Perches, promulgated in about 1300, tried to make it clear:
'It is ordained that . . . 12 inches make one foot, three feet make one yard, five yards and a half make a perch, and 40 perches in length and four in breadth make an acre.'
As if that wasn't complicated enough, there was an alternative version. Other sources suggest that an acre was simply the amount of land tillable by one man with one ox in a single day.
Fifteen acres made an oxgang. Two oxgangs made a virgate, and four virgates made a carucate. Don't worry, there won't be a test.
By contrast, pints — and you may need one by now — seem to have come with the Normans. The word derives from the Old French pinte, which scholars think comes from a Latin word for the marks painted on a container to show the level of liquid.
As usual, though, the precise definition is more complicated. An imperial pint measures 568ml, more than an American pint, but less than a Canadian pint, an Australian pint, a Scottish pint or an old French royal pint.
Inches are another Roman borrowing, deriving from the Latin uncia, meaning a twelfth. The earliest English reference, though, seems to come from the Anglo-Saxon Laws of Aethelberht, a law code setting out various punishments. So if you inflicted a knife-wound an inch deep, you were fined a shilling.
An inch, it says, is 'three grains of barley, dry and round, placed end to end, lengthwise'. But that raises the question: how long is a grain of barley?
Although it's easy to poke fun at the vagaries of the old imperial system, it would be silly to exaggerate its defects. After all, scientists and inventors from Isaac Newton to George Stephenson found it perfectly serviceable.
And once measurements were standardised in 1824, millions of people across the world became used to a single system of feet and inches, rooted in history.
By contrast, the metric system has always had a utopian, slightly bloodless, Year Zero-ish quality.
It was basically an Enlightenment project, designed by bien pensant intellectuals who shuddered at the supposed backwardness of their predecessors, and were determined to drag their compatriots into the modern world.
They got their chance during the French Revolution. Even as the gutters of Paris ran red with blood and the tumbrils carried thousands of people to the guillotine, the new regime's servants were dreaming up a new decimal calendar, with ten days a week, ten hours a day, 100 minutes per hour and 100 seconds per minute.
The metric system was part of this same project, based around the innovation of the metre.
While the metric system dates from the age of empires after the French Revolution and was carried into corners of Europe by Napoleon Bonaparte's (inset) armies
And in the next two decades, Napoleon Bonaparte's armies carried the new system into almost every corner of Europe — though not Britain, which stubbornly held out against both Napoleon and the metre.
Oddly enough, Napoleon was not a fan of the metric system. He shared that view with the writer George Orwell, who declared in 1947 that he was against any attempt to introduce the metric system into Britain.
To Orwell, as to many of his compatriots, metric units could never compete with 'rods and acres, pints, quarts and gallons . . . units with which we are familiar'. Britain, he thought, would 'be slightly poorer without them'.
Indeed, in Orwell's great anti-utopian fable Nineteen Eighty-Four, there is a telling scene when an old man tries and fails to order a pint in the pub.
'You telling me you ain't got a pint mug in the 'ole bleeding boozer?' the old man says in disbelief.
'Calls 'isself a barman and don't know what a pint is! Why, a pint's the 'alf of a quart, and there's four quarts to the gallon . . . We didn't 'ave these bleeding litres when I was a young man.'
Orwell would surely have applauded metric martyrs such as the Sunderland market trader Steve Thorburn, who was infamously prosecuted in 2000 for selling fruit and vegetables in pounds and ounces. But by that stage the battle was largely lost.
Keen to embrace European integration, successive governments had been pushing manufacturers to use metric units since the early 1960s. And today there are only a few vestiges of the imperial system left.
But if anybody seriously wanted to distance themselves from pints and miles because of some perceived association with the British Empire, they wouldn't just be demonstrating their ignorance of history. They would be ignoring one of Oxford University's most famous achievements.
Take a stroll from the Oxford University science buildings to the running track at Iffley Road, and you'll see a plaque on the wall.
It was here, on May 6, 1954, that the 25-year-old Roger Bannister achieved what had once been thought impossible — running the world's first sub-four-minute mile.
It was, he said afterwards, the dream of a lifetime. 'I found longer races boring,' he explained. 'I found the mile just perfect.'
Not the 1.6km. The mile.