A Mile Wide

If you’re thinking about ways to insult people, saying they don’t understand something very well can be a really good way to trigger someone’s tiny hairs. I’ve even heard people express their frustrations by saying that someone’s knowledge is an inch deep and a mile wide.

This phrase seems to have been helped along by a journalist named Bill Nye (no, not that Bill Nye), writing about the Platte River—an important waterway that flows along the Oregon Trail through Nebraska and Colorado. The name Platte was given to it by the French; plat means “flat” en francais, and those early European explorers must have been impressed with just how flat this river was.

When Nye wrote about it in 1889, he described the River Platte like this:

The Platte river is a queer stream. It has a very large circulation, but very little influence. It covers a good deal of ground, but is not deep. In some places it is a mile wide and three-quarters of an inch deep.

Saying someone is three-quarters of an inch deep is a cut-down! You’re saying their ideas aren’t likely to have much influence, like a river flowing steadily over a rock in the sand for a thousand years. The slow current is unlikely to dislodge even the most lightly embedded rocks.

By contrast, a rapidly moving stream can’t really be wide. This narrowing of the waterway allows much more volume to pass through quickly, cutting into rocks at the bottom with a great deal more force.

The saying that has gradually evolved from Nye’s observation about the Platte has boiled down to something like an inch deep and a mile wide. When you say this, you’re saying someone is shallow, like that stream that doesn’t have any depth.

This implies that they won’t get anything done in life, since a stream has to be deep in order for enough water to pass through it, or so the idea goes.

We can actually use a little bit of math to figure out whether or not this cut-down makes any sense. Ohm’s Law addresses this idea directly, albeit by way of electrical currents, not the flow of water down a stream. Nevertheless, this simple formula describes the fundamental idea quite well:

V = I x R

V is the voltage, or how much force is being used to push the current through the river. This is like the difference between a trickle and a firehose—how powerful the flow of water is.

R stands for resistance, and it’s like how narrow the stream is. The wider the stream, the less resistance for that water to flow. I is for current, which just goes to show how bad physicists can be at naming things.

It’s too early for math. I get it.

Even still, you can see that there are only two things that determine how fast the water will flow, and those two things are resistance and force (voltage). By simply understanding the makeup of how water flows, you can do wonderful things to it and make predictions. You can channel it and use it and redirect it.

I oversimplified things a bit when I said that the wider the stream was, the less resistance there is for that water to flow. That’s certainly true in a vacuum, but we’ve already pointed out that a stream can be either deep or wide, or both.

That means that just as much water flows through a deep stream as through a wide stream, given equal volumes.

In other words, maybe the phrase that Nye helped to popularize 135 years ago isn’t an insult at all. Maybe being an inch deep has its benefits, especially if you can become a jack of all trades, so to speak. Becoming polymathic has its benefits.

When we think about the pursuit of learning, we often think about knowing a lot about a subject. That strikes us as impressive because it takes a long time to get deep knowledge in a particular field, often years (or decades) of invested time.

By contrast, it seems too easy to learn a little about this subject and a little about that one. It doesn’t seem like we are putting in the hard work that we need to understand the world, but the truth is that sometimes it’s much easier to go wide than to go deep. Width allows you to connect things together much more easily.

The next time you think about doing a deep dive into a topic you’re interested in, think about this other type of knowledge for a moment. Consider how knowing a tiny bit about a wide range of subjects can be beneficial beyond its boundaries, with the knowledge cross-fertilizing and amplifying across fields. Think about being at a cocktail party and only knowing about one subject.

Life tends to take us all around the world, and we don’t always have our hands on the wheel, so we might end up spending a decade or two on one particular subject. Is your own knowledge base very deep, very wide, or somewhere in between?