Seven Plus or Minus Two

Life is a choice. Or actually, a series of choices. From the moment you woke up today, you made hundreds – probably thousands – of decisions, some small, some big, that will shape the way your day turns out… and that will influence, in some way, every day that follows.

So it’s worth thinking about how we make those decisions, and how we can help others make better decisions.

If you work in the creative field (and I suppose that you do, since you’re reading this,) this is important stuff. Especially if your work is in any way interactive (think: website design, museum exhibits, software development, instructional design, and so forth.)

First, let me give credit where credit’s due. Some of the ideas and info here come from RadioLab, the coolest and smartest program on radio and podcast. You can check it out at For that matter, I’m indebted to RadioLab and its hosts, Jad Abumrad and Robert Krulwich, for many of the ideas swirling around in my head, and in articles I’ve written, past and future. So there you go.

A reality of life in the 21st century is that we’re bombarded every day with an overwhelming number of choices. Which pants to wear today. What to eat for breakfast – cereal or Pop Tarts? Which route to take to work. Whether or not to stop at the dry cleaner. Whether to have kids. Or look for a new job. And so forth. How do we choose?

Start with a quick primer on the way the brain works. In the 1950s a psychologist by the name of George Miller did a series of memory tests. He was trying to figure out how much information the human brain can hold at any one time. What came out of that was a study called  “The Magic Number 7” which said, basically, that the average human can hold seven digits plus or minus two at any moment in working memory (meaning, top of mind). Did you ever notice that phone numbers, social security numbers and bank accounts are usually 7 +/- 2 digits? It’s not a coincidence.

So what happens to decision making when you try to get more than seven things in your head at once? In another famous experiment, subjects were asked to memorize a number and then recite it. Some subjects got a two digit number, while others got a seven digit number. In the hallway on their way to recite their number, each subject was offered a snack – either chocolate cake or fruit salad. Those with seven digits in their heads chose the cake by large margins. Why in the world would that be? It turns out that the brain is anatomically organized into dual systems: A rational, deliberative system in the front (called the prefrontal cortex) and an emotional, subconscious system deeper inside the brain. The rational and emotional parts of the brain are in perpetual struggle, vying for attention. The emotional part would love to eat cake, but the rational part knows you should eat healthy. When the brain is full with seven digits, the rational part (which is fully taxed) is overpowered and the emotional part wins.

In essence, having too many choices short circuits the prefrontal cortex. It forces a person into one of two uncomfortable responses: (1) Make an emotional choice and then lament the fact that you may not have made the best choice, or (2) simply make no choice at all.

Let’s apply this to the real world. Consider this website:

Yubo Screenshot

Seven main choices on the home page. Very manageable, right? Makes you want to jump in and check it out.

Now consider this website:

Comcast Screenshot

Yikes! Where do we even begin? We are bombarded with at least 16 choices, right from the start. Kind of makes you want to run away.

There is much to be said for keeping it simple. Albert Einstein put it this way: “Everything should be as simple as possible, but never simpler.”

Choice is both emotional and logical. There is the story of a guy who had a brain tumor that led to surgery that cut off the emotional part of his brain. He became entirely rational. And from that point on he couldn’t make even basic decisions… such as which pen to use. He would just keep analyzing and analyzing. The brain relies on both its rational and emotional parts in order to make good decisions.

We can help that process along, by practicing good interactive design.

Bill Haley
Bill Haley
Bill Haley is a founder of He is also President, Interactive of Allied Pixel, an integrated media production firm that connects the dots between HD video, web and interactive media.

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