Subtract summary

Like Sue Bierman, the author’s own journey into subtraction also began with architecture. It all started when the author and his little boy were building a Lego bridge, and the bridge’s supporting pillars ended up being different heights. Instinctively, the author picked up another block to add to the shorter pillar. 

At that moment, the author had a startling realization: it would never even have occurred to him to take away a block from the taller pillar. Could this be an indication of something bigger, he wondered? Might it be that human beings overwhelmingly add rather than subtract? 

So, human beings tend to overlook subtraction. But the question remains: Why? Perhaps the behavior of another species might suggest an answer. 

Male bowerbirds also do a lot of adding. But they don't add soup ingredients or Lego blocks. Instead, they add sticks, leaves, and colorful objects to their nests – bowerbirds are the showy architects of the bird world. What's more, a lot of this addition seems arbitrary. The bowerbirds never use these nests. As soon as the female has decided which complicated nest she likes the most, she mates with the male who built it, and then they leave the palatial nest behind. 

Our journey into the science of adding and subtracting now takes us to Turkey – specifically, to an archaeological site called Göbekli Tepe. What archaeologists found here shows us that adding isn’t just a biological instinct that we share with other animals. Instead, adding might be the driving force behind human civilization itself. 

So what incredible wonder is Göbekli Tepe hiding? The answer is an ancient stone temple. This temple is an extremely early example of monumental architecture, a type of building whose sheer scale and intricacy goes far beyond what is necessary for its purpose. 

So we’ve inherited our ancestors’ preference for adding. But there’s also a very modern reason why we prefer to add rather than subtract: our economies demand it. And not only do modern capitalist economies encourage us to add – we’re also urged to think of constant adding as a good thing. 

But what do economics, addition, and morality have to do with one another? 

Before any subtraction happens, there needs to be understanding – after all, you have to know all the constituent parts of the thing, or situation, that you want to change. Only then can you make informed decisions about which parts to take away. That’s because a lot of the things we want to change don’t exist in a vacuum; they’re complex systems that are more than the sum of their parts. 

To demonstrate this point, let’s take a look at something that many people would like to change: racism. Author Ibram X. Kendi argues that all racism is systemic racism because the systems that govern our lives, like the justice system, are innately racist. Racism is so difficult to “subtract” because most people don’t fully understand how these systems perpetuate it. 

You may have heard the expression, I’ve written you a long letter because I didn’t have time to write you a short one. This pithy remark has been attributed to the author Mark Twain – but it could have been written by any one of us going about our daily lives. That’s because it gets at an essential truth: subtraction is hard work. 

Whether you’re chipping away at a concrete freeway or a wordy sentence, cutting out the unnecessary to arrive at something better takes much more effort than just leaving things as they are. It's easier to walk away when something’s “good enough.” After all, that short letter probably would have been better, but the longer one did the job, too.