Little Things

My grandmother was fond of nursery rhymes, which may account for the fear I carried with me when I was a child. Very young minds have difficulty grasping the sophisticated logic of many nursery rhymes, and the underlying message—generally a lesson of colossal import—is just as likely to soar over the youngster's head.

Early this morning, as I sat pondering the absurdity of the minutiae responsible for the catastrophic failure of complex systems, my grandmother's voice burst into my consciousness. One of my earliest memories sprang again to life, bringing a nursery rhyme I haven't heard since I was a child. At the time, the verse held for me no discernable meaning; I only knew it was ominous in some implicit way. My legendary fear of horses hadn't yet manifested at that age, so that didn't figure into it.

For want of a nail, the shoe was lost;

For want of the shoe, the horse was lost;

For want of the horse, the rider was lost;

For want of the rider, the battle was lost;

For want of the battle, the kingdom was lost;

And all for the want of a horseshoe nail.

The concept of cause and effect is a valuable lesson indeed, but the devil is in the details and sufficient detail is something the average nursery rhyme lacks. Certainly, every systemic failure has its causes, and any genius can stand and point at the smoldering pile of goo afterward. Really, what's important isn't so much that the system failed, but what might have been done to prevent it. Who was in charge of inspecting the nails to make sure they were suitable for use in horseshoes? Was the nail faulty, or was it the shoe itself? Where was the pit crew when the time came to swap those old shoes for fresh ones? What did the veterinarian do to get the horse back on its feet? And how much did the rider weigh?

In fact, everything is a system, and sometimes the cause of the failure is nothing more than the lack of a nail. But other times, the problem has more to do with a tragic lack of understanding on the part of those who make the crucial decisions. The rider may look okay, but that doesn't necessarily mean the horse has eaten lately. Sending the pair into battle, then expressing surprise when the horse drops dead—killing the rider in the process—isn't a very good excuse for losing an entire kingdom.

And in the end it's the king who loses his head, even when it was one of his generals who decided that horses can function perfectly well with no shoes at all.