That Very Special K

By The Metric Maven

Special K

In my teenage years, I, like many of my contemporaries would stop at an A&W Drive Inn for a root beer and food. One day my friend Rick asked one of the car hops, “what does A&W stand for?” The car hop looked puzzled and indicated she didn’t know. It became an oft-used way to attempt to initiate a conversation with the car hops, who were exclusively female in those days. Not one of them knew the answer.

My youngest sister began working at an A&W during my High School years, and when she had the misfortune to have me as a customer, I asked the question. She looked at me with a countenance which indicated how sophomoric, obvious, and slightly irritating the question was. Then she replied “Allen and Wright.” I was dumbfounded; she was the first to know. “How did you know I asked?” Her instant reply was “It’s on the checks.”

Another question is “what does the K in Special K stand for?” The Wikipedia page on Special K is of no help. Never fear, because on the internet you can always find an “answer”—no matter how much of an urban legend it might be. The first offering is that it stands for Kalium, which is Potassium, and was the essential nutritional addition that was touted as an important part of your healthy diet. What is the symbol for Potassium in the periodic table of the elements? Why K of course!—a capital K! Well, when folk origins are offered, they can be interesting, or prosaic. The internet then alternatively claim’s the K is for Vitamin K! A more down-to-Earth suggestion is that, well, the K stands for Kellogg’s, the manufacturer, and eponymous identifier for one of the Kellogg brothers.

That’s a lot of capital K’s to sort out, and as you might have guessed this essay is about the strange and illogical use of lower case and upper case k in the metric system. The idea that a lower case k should be used for Kilo, whereas all magnifying prefixes above Kilo, are upper case, makes exactly zero sense. It makes such little sense, that I’ve seen it in a high school chemistry textbook defined as capital K, which in the odd BIPM universe would be a “typo.” I see speedometers on the dashboards of Japanese bullet trains that have Km/hr, and other examples where the intuitive usage, capital K, is implemented, rather than the ecclesiastical usage.

When I challenged the use of lower case k as the prefix symbol for Kilo, Metric Bishops scampered out of the woodwork with justifications for this confusing usage. I was told that the lower case k was to remind everyone that SI is essentially the mks system, and so the kilogram is the base unit, and not the gram. This seemed one of the least useful reminders ever. So the kilojoule kJ, kilometer km , kilosecond ks , kilonewton kN—and so on—must all also be lower case? They are not base units. But Megajoule MJ, Gigameter Gm, Terasecond Ts, Petanewton PN and so on are all upper case? This seems absurd. No, this is absurd. It appears ad hoc and post hoc to me, and not deliberative.

Other Metric Bishops chime in with what they see as a better argument. Well, if you use capital K, it could be confused with temperature in Kelvin. Sometime back I understand the degree was taken away from K for temperature, which makes the muddle worse in my view, rather than improving it. I also have never liked the name Kelvin. Naming measurement units after scientists is essentially a national conceit. I’ve elaborated on my dislike of eponymous units in my essay Eponymous Measurement Units and Planet George. Centigrade was a perfectly non-anthropomorphic name, that was changed to Celsius after it had long been an accepted label. I would like to use milligrade, and go back to a non-person unit name for everyday temperature, and eliminate one more centi. Oh, no, no, no, we can’t use K for a prefix and for temperature!—that would be wrong—a Metric Bishop asserted. Strangely the reuse of mm for milli and meter does not cause any concern, but two upper case K’s do? Well, it has all been put in the sacred text say the Bishops, and what is done is done.

I had not given much thought about what manner of heresy might work to free metric from the dogma of the special K for Kelvin, when the answer popped right up unexpectedly. I was reading an essay about the absolute temperature scale titled “The Height of Up” in View from a Height by Isaac Asimov. Asimov states:

As I’m not for the “convention” Dr. Asimov mentions, I will go with degrees A for Absolute temperature scale. It seems to me that the term “absolute scale” is more self-explanatory than is “Kelvin scale,” and in my view unit names that suggest the meaning of a unit serve engineering and science better than the last names of historical humans. I’m sure the Metric Bishops can’t see any way that we could change from this anthropocentric nomenclature as it is “too late,” but I think it is never too late to make a rational change, like switching over to the metric system in the US. If you need a human based virtual last name to go with degrees A, then let’s go with my favorite candidate, degrees Asimov.

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