Ford Whitman Harris and exploration

In the Land of All Unquestioned and Unexplored Curiosities and Oddities and Peculiarities, once upon a time, lived Ford Whitman Harris, and he was an engineer. And it was true, Ford Whitman Harris was indeed an engineer, and he later became a lawyer too. But above all Ford Whitman Harris was an explorer. Wherever he was and whatever he did, Ford Whitman Harris explored. And he explored anything, and he explored everything. He explored drafting and engineering, and product designing and process building, and manufacturing and managing, and patenting and trademarking, and a bit boring if you ask me but must be to him exciting copyrighting.

All the things there were to explore in the Land of All Unquestioned and Unexplored Curiosities and Oddities and Peculiarities, Ford Whitman Harris explored. Till at last there was one thing left in this land to be explored. A thing that puzzled all the engineers and the managers and the engineering managers and the managing engineers of the land at the time. It was the question “What is the most economical quantity in putting through an order?” they could not answer.

And Ford Whitman Harris drew graphs and lines (because he was a draftsman), and looked at similar graphs and lines (because he was an explorer), and let his mind wander (because that’s what his mind did, he just could not help it). And he wrote equations for his graphs and lines, and looked at other equations for similar graphs and lines, and let his mind meander. And he created a most curious expression that some called the square-root equation. And this tiny and tidy, and dainty but mighty equation did not say why me, but shyly yet politely showed the engineers, and the managers, and the managing engineers, and the engineering managers of his time and my time and your time what to do, how to determine the most economical order quantity to put through.

Some learned ones later questioned how Ford Whitman Harris came up with this equation. They said that he was not a learned man, and that he had no education. They said that he did not have a degree in drafting, or in engineering, in manufacturing, or in managing. They said that perhaps he saw Kelvin’s Law of the economic size of a conductor and imitated it to determine the most economic size of an order. But does that really matter? Ford Whitman Harris knew what he knew, and he explored because he was an explorer. Whether dear Lord Kelvin inspired him or not, it was Ford Whitman Harris who solved the knot.

So, my dear reader, as you ponder how such a deceptively simple yet deeply insightful the so-called square root equation can help you see so clearly the trade-off between the fixed cost of ordering and the variable cost of inventory carrying for an order that you are planning to put through, always remember that for some problems the knowledge in your own field will suffice and for some others you may have to look to other fields for advice. Explore your field well, know its each and every nook and cranny, but do not shy away from its boundaries and do not avoid other territories. How and why we divided the knowledge of the world into different fields, no one can answer, but those arbitrary boundaries are there for you to send down under.

Explore other territories as you follow your own insatiable curiosities and endless oddities and boundless peculiarities. And continue to grow the illuminating and inviting, and surprising and inspiring, and mystifying and intoxicating, and a bit boring if you ask you but is to me most exciting labyrinths of your mind, where all ideas you ever had and you ever will have belong and that only you can explore and walk along.

PS: If this too sounds oddly familiar, then you must have read “How the Whale Got His Throat” from Just So Stories by Rudyard Kipling as well. I found this story by the way of Ursula K. Le Guin as I followed a crumb she dropped in Steering the Craft. This is yet another attempt to make some topics that I teach tell their stories. In this case, I also must thank Donald Erlenkotter, who seems to have followed many trails of crumbs to reveal the obscure and almost forgotten history of the economic order quantity model, and the interested reader should look into his published work.

Erlenkotter D (1989) An early classic misplaced: Ford W. Harris’s economic order quantity model of 1915. Management Science, 35(7): 898-900.

Erlenkotter D (1990) Ford Whitman Harris and the economic order quantity model. Operations Research, 38 (6): 937-946.

Erlenkotter D (2014) Ford Whitman Harris’s economical lot size model, International Journal of Production Economics, 155: 12-15.