There is little point in your reading any of my opinions on things, until you understand what I mean by "good" and "evil", so you should start by reading how I define these, and only then go on to read the rest of my bigoted maunderings.

Not everyone will love everything I have to say, and you will find above a link to a page telling the tale of one attempt to have my views banned, and another about how I was eventually banned.

Imperial - Huzza! Metric - pah!

The imperial system of weights and measures is on the wane. It is being replaced gradually by metric. Some of this change may be for the better, but much of it isn't.

The imperial system did not spring into existence in one moment of concerted creation, but gradually developed over many centuries. Though it may be associated with the British, who standardised it and spread it across the world, it was not a British invention, but was instead an amalgam of measures from across the world and the centuries. It has had a lot of testing, and if it were rubbish, it would have been replaced millennia ago.

In my experience, people who argue against the imperial system do so from a position of ignorance. They do not understand the beauty of imperial, nor the deep flaws of metric. They have an idea that imperial is out-dated, and metric is modern and therefore good, and they support changes to metric.

Change is not progress. Change is just change, and it can be very expensive. In Britain today, we buy fuel from petrol stations in litres, but once we did this in gallons. When the change was enforced, every petrol pump, every price sign, every fuel-measuring device, and every accounting system used for fuel, had to be changed. I shudder to think how many millions this cost, and how many hospital operations these might have paid for. What value was got for this money? It was of course massively inconvenient for everyone in Britain who had to get used to a new measure, and petrol stations did of course take the opportunity to raise prices, and almost nobody in Britain welcomed the change, so the down-side of the change was very obvious. What was the up-side? Did cars run any better?

Britain has been obliged to give an undertaking to the European Union to stop selling beer and milk in pints. Everyone here likes pints and is used to pints, but now the EU is threatening to fine Britain for continuing to sell in pints [Update 2012: the threat of the fine has now been withdrawn, thanks largely to years of obstinate refusal by the British to drop such a cherished tradition, and the EU has now admitted that the idea of the fine was silly]. Whom do we harm by selling pints? If we harm no one, then we should not be fined. Are the people of Britain harmed in any way whatsoever by being sold pints? The pint is a very simple convenient unit. The experience of centuries has gone into settling on this particular size of unit. There is nothing wrong with a pint. The only argument seems to be that it is different from the units used elsewhere in the EU.

When I go abroad, I want things to be different. If everything in Poland is the same as in Britain, what is the point of going there? Foreigners like the exoticism of Britain. They like our red telephone boxes, our tall policemen's helmets, and our beefeaters, and they go to some trouble to photograph them. When I go to Greece, I want to see big tough guardsmen wearing tutus and pom-poms, and I photograph them. Part of the novelty and interest in visiting Britain is that you can buy a proper pint of beer in a pub, or get a pinta delivered to your doorstep. Why deprive foreigners of this fun? How do they or anyone else benefit from beer and milk sold in litres? Do we think that they are too stupid to understand that units other than litres are possible?

One massive misunderstanding about the metric system is the widespread and inaccurate belief that it is based on a uniquely convenient number. In base thirty-seven, thirty-seven is a very convenient number. I've lost count of the number of times I've heard someone say that base ten is good because it is easy to multiply something by ten in it - you just add a nought. This is a completely stupid argument. To multiply any number by the base number, you add a nought. In base six, to multiply something by six, you add a nought. Indeed base six has many more convenient numbers in it - every sixth number is round, whereas in base ten only every tenth is round.

What makes a good base? What is actually a good convenient number? Well, sub-multiples are good. It is very easy to deal in these. In base ten, there are two: 2 and 5, and these are both 'prime' (generally inconvenient) numbers. In base ten, multiplying and dividing by 2 and 5 is reasonably easy. Let us compare this with base twelve. Twelve divides by 2 as well, it also divides by the extremely useful number 3, it also divides by 4 (which in turn divides by 2), and it divides by 6 (which in turn divides in to both 2 and 3). So twelve has eight sub-multiples to base ten's two. This means that at least four times as many sums in base twelve will involve convenient numbers as in base ten.

What about base twenty-four? Here are its sub-multiples:

12 (6 (3, 2), 4 (2), 3, 2)
8 (4 (2), 2)
6 (3, 2)
4 (2)
3
2

That's nineteen sub-multiples. Another useful thing that bases can help us with is geometric progression. Base sixteen is very convenient for halving or doubling. Think of the sequence 1, 2, 4, 8, 16. Mathematicians use base sixteen (they call it "hexadecimal") not because they want to appear clever, but because it is an easier base to work in than grotty old base ten.

Something of the insignificance of the number ten is preserved in the fact that languages have unique words for numbers beyond ten. Almost every language is like English in having words for eleven and twelve. Twelve is a very common number of sub-divisions for a unit (e.g. inches to a foot, pennies to a shilling). We say 'twelve', not 'twoteen' or 'onety-two'.

You may argue that metric is based not on the number ten, but more on the number one hundred. There are one hundred centimetres in a metre and so forth. Perhaps most importantly, there are one hundred sub-parts to most currencies (cents to a dollar, for example). Well, actually 100 doesn't rate too highly as a number either. Let's look at it's sub-multiples:

50 (25 (5), 10 (5, 2), 5, 2)
25 (5)
20 (10 (5, 2), 5, 4 (2), 2)
10 (5, 2)
5
4 (2)
2

That's a very poor haul of sub-multiples for such a high number. The fact that it doesn't divide nicely by three is a major drawback. In the old British pound, there were 240 pence. Some people laugh today when they hear this, thinking quite wrongly that this is a difficult number. No it isn't. There were 240 pence in an old pound for a very good reason. 240 is a very convenient number. Brace yourself for its sub-multiples:

120 (60 (30 (15 (5, 3) 10 (5, 2) 6 (3, 2) 5, 4 (2), 3, 2), 20 (10 (5, 2), 5, 4 (2), 2), 15 (5, 3), 12 (6 (3, 2), 4, (2), 3, 2),10 (5, 2), 6 (3, 2) 5, 4 (2), 3, 2), 40 (20 (10 (5, 2) 5, 4 (2), 2), 10 (5, 2), 8 (4, 2), 6 (3, 2), 5, 4 (2), 2), 30 (15 (5, 3) 10 (5, 2) 6 (3, 2) 5, 4 (2), 3, 2), 24 (12 (6 (3, 2), 4 (2) 3, 2), 8 (4, 2), 6 (3, 2), 4 (2), 3, 2), 20 (10 (5, 2), 5, 4 (2), 2), 15 (5, 3), 12 (6 (3, 2), 4 (2) 3, 2), 10 (5, 2), 8 (4, 2), 6 (3, 2), 5, 4 (2), 3, 2
80 (40 (20 (10 (5, 2) 5, 4 (2), 2), 10 (5, 2), 8 (4, 2), 6 (3, 2), 5, 4 (2), 2), 20 (10 (5, 2), 5, 4 (2), 2), 16 (8 (4, 2), 4 (2), 2), 10 (5, 2), 8 (4 (2), 2) 5, 4(2), 2)
60 (30 (15 (5, 3) 10 (5, 2) 6 (3, 2) 5, 4 (2), 3, 2), 20 (10 (5, 2), 5, 4 (2), 2), 15 (5, 3), 12 (6 (3, 2), 4, (2), 3, 2),10 (5, 2), 6 (3, 2) 5, 4 (2), 3, 2)
48 (24 (12 (6 (3, 2), 4 (2) 3, 2), 8 (4, 2), 6 (3, 2), 4 (2), 3, 2), 16 (8 (4, 2), 4 (2), 2), 12 (6 (3, 2), 4 (2) 3, 2), 8 (4 (2), 2), 6 (3, 2), 4 (2), 2)
40 (20 (10 (5, 2) 5, 4 (2), 2), 10 (5, 2), 8 (4, 2), 6 (3, 2), 5, 4 (2), 2)
30 (15 (5, 3) 10 (5, 2) 6 (3, 2) 5, 4 (2), 3, 2)
24 (12 (6 (3, 2), 4 (2) 3, 2), 8 (4, 2), 6 (3, 2), 4 (2), 3, 2)
20 (10 (5, 2), 5, 4 (2), 2)
16 (8 (4, 2), 4 (2), 2)
15 (5, 3)
12 (6 (3, 2), 4 (2) 3, 2)
10 (5, 2)
8 (4 (2), 2)
6 (3, 2)
5
4 (2)
3
2

There were very few money transactions that did not involve convenient numbers. Items could be sold in packets of a lot of different convenient numbers too, like eight or twelve. Notice that out of the basic numerals 1-10, only 7 and 9 do not divide into the pound. What is a tenth of a pound? Easy: 24 pence, which was one florin, or two shillings, and these could be subdivided many easy ways. Dealing with the number ten was easy with old pounds just as it is with new ones. Programming a modern pocket calculator to deal in imperial units would be easy too, and would be done today if the demand were there.

People today are not experienced in using the number 240, and so don't know how great it is. Europeans, long-blighted by the metric system, say that 100 is convenient out of sheer ignorance. However, it is possible to make them understand how good some numbers other than 10 and 100 are by pointing out that they have not metricated everything. A European circle still has 360 degrees, and a European day still has 24 hours, each of 60 minutes.

360 is another excellent number, like 240 it has a vast number of convenient sub-mulitiples. Anyone who has done much geometry will know that sub-dividing a circle is greatly eased by the number 360. Anyone who has ever had to draw up a time-table knows that both 60 and 24 are very convenient numbers. Would you really like days to have ten hours, made up of ten decihours, or one hundred centihours? You couldn't even have three lessons an hour in the school day without dealing with awkward fractions.

The Babylonians spotted the virtue of 360, and it is thanks to them that we have this number of degrees in a circle. In parts of the Middle East today, people are still using base 6. Base six has a number of convenient features, one of which is that a person can count on one hand to a very high number, using the hand's five digits as the numerical digits, and indicating various joints in the fingers etc. to show the sixes.

Errors in calculations using metric are untraceable, and easy to make. You could quite easily make one slip in a calculation, and be out by a factor of 100, and if common sense will not tell you that you must be wrong, then you may not notice your error, and if you try to trace where it crept in, you will fail and have to start again. "That's odd," you might otherwise think, "I seem to be out by a factor of twelve. Ah of course - I forgot to convert inches to feet."

Yes, for some scientific calculations involving units measuring different things, such as time, mass and velocity, a system that involves all units having the same base is convenient, although the days of that convenience may have passed, since today computers could very easily be programmed with the different units, and this would force people to think of each part of a calculation, and would if anything reduce errors. I doubt such calculations are done by hand very often today. I wonder if it is a coincidence that America, the only country still consistently using imperial measures, is so technologically and economically successful.

The imperial system has much to recommend it. Linguistically it is pleasant. Rather than everything starting with deci-, kilo-, or centi-, and ending in -re (or -er in the USA), there are many different old words, that tell of times past. In metric all distances end in -metre, but imperial has inch, foot, yard, chain, pole, furlong, mile, and league. The numbers these divide into are nice convenient ones, like 3, 12, 16, 36, 220, and 1760. The sizes of these units are convenient too. Estate agents still prefer to measure rooms in feet, because this is the right size of unit for the job. My shoes happen to be one foot long, so I can pace out a room very accurately, and someone with slightly larger or smaller feet could soon learn how much gap to allow for the difference. In metres, rooms tend to seem exaggeratedly different or similar in size, because there is so little variation in the first numbers. For this reason, architects and set designers in Britain and I believe elsewhere in the world have adopted a metric foot (one third of a metre) for working in. Similarly, a person's height is conveniently measured in feet and inches. Less than five foot is short, over six foot is tall, and there are twelve gradations in between, which makes estimating height very easy. In metres, everyone is one-metre-something. The British climate suits Fahrenheit more than centigrade, because there is not much variation in the latter.

Navigation all round the world is done using imperial units. Headings are in degrees, and distances in nautical miles. This is unlikely to change, because unlike metric, imperial units tend to refer to actual physical things, rather than an abstract concept, and the nautical mile is a convenient fraction of the distance around the Earth, and relates to degrees of longitude and latitude.

The metric system is based on a false and rather useless measurement. The metre, from which everything is derived, is supposedly one ten-millionth of the distance between the equator and pole. The distance used for this calculation was based on a Napoleonic French estimate which has since proven inaccurate. This distance was also nearly one yard, but rather than adopt the yard (a unit well-known to everyone) and relate everything to that, the revolutionary French wanted change for the sake of change. It was a political statement: they were starting anew. It is for this reason (and to impose change to show their power) that they forced everyone to drive on the wrong side of the road. Today, there are plenty of figures to show that people's natural inclination is to drive on the left, and countries that drive on the left have far lower accident rates.

One item of praise I have heard for the metric system is that there is cross-over between capacity and weight, in that one litre of distilled water at sea level weighs one kilogram. This is very convenient when estimating the weight of distilled water from a known volume, and seldom otherwise. Anyway, one gallon of water weighs ten pounds, so the imperial system crosses over too.

The width of my thumb is one inch, the width of my hand is four inches, my feet are a foot long, my arm span is one fathom, I can pace a yard, my fist and forearm are one cubit long, a field is one furlong across. I live in a world in which I can measure and estimate in imperial very easily. I was interested to learn that even the French did cel animation and rostrum camerawork using inches, because halving distances in imperial is so much easier.

Is the imperial system flawless? Good lord, no, of course not. One criticism I have of it is that a stone divides into fourteen pounds, and fourteen is not a convenient number, as it is not easy to divide or multiply by it, and it only subdivides into two and seven, which are both prime numbers, making it is only slightly better than ten (by having more gradations).

In case you didn't believe me.

Let us preserve the imperial system. It needn't be frozen in time. It has changed many times in the past, and more changes can be made to it. It is a good system, made up of convenient measures. Jam and honey in Britain are still sold in one-pound jars, but now they have to be called 454g jars (another common jar is the 12oz jar, or 340g). It is actually illegal to tell people that a jar weighs a pound [Update 2012: it is no longer illegal to tell people that a jar weighs a pound, but it is still illegal to sell them the jar once you've told them]. Why? Who benefits from this law? It is easy to see who suffers. The only people I can think of who benefit are the people whose job it is to enforce this.

It isn't just that it's a good system. It isn't just that it will make people think more. It isn't just that changing from it is pointlessly expensive. It isn't just that it's our system (now that most foreigners have ditched it). It's also that it is characterful. Life is made more worthwhile if the characters in it are interesting and different rather than bland, predictable, and ugly. The metric system does not relate to the real world, is utterly characterless, and it's French.

This piece was on this website for many years (I wrote it in about 1998-2000 I think) before being spotted by the British Weights and Measures Association, and it appeared in issue 51 of The Yardstick 2012.