I only bring this up because I’m fascinated by the degree to which brains have evolved to become more powerful than guns. Society’s founding geniuses engineered a social system that encourages the young people who have guns to shoot at each other instead of robbing old people. Forgive me for calling that awesome. Arguably, the most important function of human language is to protect the smart from the strong. Humans use words to create sentences, and sentences to create concepts, such as our notions of duty and honor. Powerful concepts control behavior. Without our language and concepts, the strong would kill the smart, and humans wouldn’t evolve to be any smarter. I think you could say that human evolution is being guided at least partly by the power of ideas.

The word “capitalize” comes from “capital,” meaning “head,” and is associated with importance, material wealth, assets and advantages. We have capital cities and capital ideas. We give capital punishment and accrue political, social and financial capital. And then there is capitalism, which is linked to private ownership, markets and investments. These words shore up the towering single letter that signifies us as discrete beings and connote confidence, dominance and the ambition to pull ourselves up by our own bootstraps.