The other day, I was reading a post on Linkedin in which the author was refuting the message of another post/article. Among the criticisms was that the author used millions of kilograms instead of thousands of tons to sensationalize and influence opinions. That got me thinking.
It is true that we have used numbering to influence perceptions, and prices at $9.99 instead of $10, or car payments of $50 per week instead of $200 a month, have become basic marketing and communication gimmicks. So it is normal to extend that to 2 million kg of CO2 instead of 2000 tons to shock people. Since I had some spare time and spare space in my brain, I got thinking: ” is that the only reason? Would there be a better justification for using kilograms here rather than tons? " And I could think of one, which got me to the notion of primary units and secondary units of measure.
You see, most people have a sort of innate understanding of what a kilogram (or pound for imperial systems users) is or feels: we buy food in kilograms, liters and meters (or portions thereof), we lift kilograms of weight at the gym, and we measure ourselves in kilograms and meters/centimeters. So a kilogram, meter, liter (or pound, inch/foot, gallon) speak to us without having to convert it to anything else. When someone says 2 million kilograms, I can almost feel the immensity of that weight directly without needing to interpret it.
Now, when someone says 2000 tons, I am not sure if it is as direct. I know a ton is a lot, but I cannot feel it. I would have to think (and all this is done unconsciously) a ton is a 1000 kg, or that a standard car weighs 1,5 tons so 2000 tons is equal to about 1300 cars, and that I can feel. So for me to understand the enormity of 2000 tons, I have to convert it to something I can feel, for I have never carried nor lifted a ton of anything.
And this is how I got to the notions of primary units and secondary units. Not in a scientific notion of primary/secondary, but in a human comprehension notion, where the primary units imply an almost innate and natural understanding of what it implies, and the secondary ones, which are generally used to simplify the expression of large numbers but cannot be “felt” by humans unless translated into something innate and primary.
But, I presume someone long ago has thought about this and there may even be an entire discourse on this topic.
Paris, October 21, 2021,
Zeejay