I’ve been to numerous talks on software measurement and metrics, and it seems inevitable that the instructor quotes this guy named “Lord Kelvin.” I finally decided to figure out who this guy is and see how he is related to software measurement. I found out that Lord Kelvin was a physicist named William Thomson. According to the Wikipedia, “He was ennobled in 1892 for his achievements in thermodynamics, and of his opposition to Irish Home Rule and became Baron Kelvin of Largs in the County of Ayr. He was the first British scientist to be elevated to the House of Lords, and Kelvin refers to the River Kelvin that flows close to his laboratory at the University of Glasgow.” Being in the House of Lords + Baron Kelvin = Lord Kelvin. With his scientific research in the laws of thermodynamics, absolute temperatures are stated in units of kelvin in his honor. Although the existence of a lower limit to temperature (absolute zero) was known prior to his work, Lord Kelvin is widely known for determining its correct value as approximately −273.15 degrees Celsius (-457 Fahrenheit). 

So why is this guy in the teachings of software measurement and metrics? Well, he did make a lot of very relatable quotes in scientific journals and as a professor. Here are a few quotes that are often cited in and applied to software measurement:

  • “To measure is to know.”
  • “If you cannot measure it, you cannot improve it.”
  • “The more you understand what is wrong with the figure, the more valuable the figure becomes.”

Those look like sound bites from a political campaign! What I like more are some of this deeper quotes that apply to many things:

  • “When you can measure what you are speaking about, and express it in numbers, you know something about it; when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind. It may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science.”
  • “You can understand perfectly if you give your mind to it.”
  • “When you are face to face with a difficulty, you are up against a discovery.”
  • “The true measure of a man is what he would do if he knew he would never be caught.”

So, on software measurement and Lord Kelvin, I guess they do go together. I suppose that when he was determining the absolute coldest temperature, he really had to be precise and have a deep understanding of measurement. My hats off to Lord Kelvin!