The Metric System

Despite the idiocy of many humans, humanity itself continues to improve at most things. Technology, medicine, quality of life, access to information, productivity, and almost everything else we accomplish as a species is better now than it was before, and will be better in the future than it is now. However, sometimes we make mistakes and actually go backwards. Here I will cover a giant leap in the wrong direction made by nearly the entire world -- the metric system.

To give you an indication of just how widespread this mistake was, according to Wikipedia, the only countries that do not use the metric system as their primary system of measurement are the United States, Liberia, and Myanmar. That makes those three countries the three smartest in the world. There are many advocates in the United States for migrating to the metric system. Fortunately, common sense has thus far prevailed, and it remains a beacon of sanity in an insane world.

So what's wrong with the Metric system? It's simple. It was designed for scientific use in laboratories, equations, etc. It was not designed for every day use by the majority of the population. This is made obvious for a number of reasons across many of the different units of measure.

Metric units are not magic

First, let's agree that all base units are arbitrary. Here's how the metric units are defined:

• Meter - the distance travelled by an object moving at the speed of light for 1/299,792,458 of a second. And how was that number decided upon? It was an approximation of 1,650,763.73 wavelengths in a vacuum of the radiation corresponding to the transition between the levels 2p10 and 5d5 of the krypton-86 atom. So what about that number? Well, it was just about equal to a platinum bar in France, when that bar is at a specified temperature and pressure, and is supported by two rollers. How did they figure out how long of a bar to make? It was just about 1/10,000,000 the distance between the North Pole and the Equator. That number was arbitrary.

• Kilogram - the weight of a piece of metal in Paris. How was this weight decided? Well, it went through several revisions, but was essentially based on the weight of a cubic decimeter of water at 0 degrees Celsius in a vaccuum. That number was arbitrary.

• Ampere - 6.241 * 10 to the 18th power of the electric charge of a proton. This number was derived from the current that would deposit 0.001118000 grams of silver per second from a silver nitrate solution. That number was arbitrary.

• Celsius - -273.15 degrees Celsius is defined as absolute zero and .01 degrees Celsius is defined as the triple point of water. That number was based on the freezing and boiling points of water at a pressure of one atmosphere being valued at zero and one-hundred, respectively. These numbers were not so arbitrary as those previous, but, as I will demonstrate, even they are not good numbers for common use.

• Most other units are based on relating the above units to each other.

For the remainder of this argument, I am going to be comparing the metric system to the imperial system used by the United States. I am not going to list the origins of imperial units because their history is not important. What is important is to demonstrate how the imperial units are at least based on useful approximations. I will tackle the different units in the same order as listed above.

Length

In regards to the meter, how often does your average person need to know how far light travels in an infintesimally small amount of time? Or when are they measuring the wavelengths of atomic radiation? More practically, when are they calculating the some fraction of the distance between Earth's North Pole and its equator? I'm going to go with never, never, and never on those.

The imperial system has units such as a foot, which is about the length of a human foot. Three of those are defined as a yard, which works out to a distance very close to a human stride. If you need more precision, you have inches, which are large enough that they're easy to eyeball and small enough that they're plenty precise enough for most tasks. Additionally, they're easy to map to fractions of a foot, which is something I'll get into later.

For longer distances, you have miles, which were originally defined as 1000 paces. An arbitrary number? Sure. But a useful arbirtary number. It was used heavily by travelers and militaries on the march. That's the key difference between metric and imperial. The former is meant for science, the latter is meant for practical use.

Do me a favor. The next time you're drawing out a makeshift baseball diamond, see what's faster: locating a meter stick or tape measure (or running out to procure one if you don't have one handy), or counting your strides. Which was faster? Easier? Cheaper?

Mass / Weight

The pound was defined in terms the weight of 7,000 grains of wheat, which was used heavily in trading. Now, it's defined in relation to a kilogram, making it equally as arbitrary as a kilogram. The big difference is that a pound is made up of 16 ounces, and a kilogram is made up of 1000 grams, and the 16 is more useful than the 1,000, which I will explain later on.

Electric current

Not applicable. There is no imperial unit.

Temperature

Let me ask you this, outside of science class or, if you are a professional scientist, your job, in what context are you referring to temperature the majority of the time? I'm going to guess that the answer, overwhelmingly, is the weather. But Celsius is not defined in terms of the weather, it's defined in terms of the physical states of water. You know what is defined in terms of weather? Fahrenheit. The scale of zero degrees to one-hundred degrees maps very closely to the liveable temperatures of the human being. When you go above or below that range, human life starts to become dangerous without accounting for those extremes.

When given a temperature in Fahrenheit, you can very quickly map that to a general weather forecast. You have a one-hundred point scale where numbers in the middle imply mildness and numbers closer to either end are your measures of hot and cold. Tell me how often one-hundred degrees Celsius comes up in your life.

Conversions

The most commonly made argument for the metric system is how easy it is to convert from one unit to another. A meter is 100 centimeters. A liter is 1000 milliliters (never mind how unuseful a single milliliter is to anything practical). So all you have to do to convert is move the decimal. This works well if you're writing numbers on paper, but let's say you're doing some woodwork, and someone says, "Cut me a third of a meter." 0.33333 repeating meters is not intuitive, so let's convert that to centimeters. Now you need to cut 33.33333 repeating. That's not any better. If someone says, "Cut me a third of a yard," your response would probably be, "So, a foot?" A third of a foot? Four inches. How is that not an easier conversion?

The metric system's conversions have nothing to do with practicality, and everything to do with how many fingers are on the hands of the average human being. But if you're doing math in your head, 12 is a lot more useful than 10. It's divisible by 2, 3, 4, and 6. Ten, on the other hand, is divisible by 2 and 5. So even the most prominent argument for the metric system breaks down once you take it outside the laboratory. There's a reason steaks come in 6oz, 8oz, 10oz, 12oz, or 16oz increments and not whatever those work out to in grams. Because they're useful values that convert to easy fractions of a pound.

Conclusion

That the metric system is better than the US Imperial system is a commonly accepted argument that very few people apply any real analysis too. This is problematic because that argument, in nearly every context in which it is made, is wrong. Metric works well in a scientific setting, but in real life application it falls short. Its measurement values just aren't based on common use cases. The United States is correct in continuing to use the Imperial system, even before you factor in the cost inherent in making the switch.

The metric system, as an every day system of measurement, sucks.