Why We Can’t Actually Walk and Chew Gum at the Same Time

When it comes to how we spend our time, Americans are a walking paradox.

On the one hand, we value choice. From the professions we choose to the myriad work arrangements we increasingly allow in our workplaces, Americans like to think that ours is a nation where getting ‘er done is that much more important than putting in the hours.  At the same time, we are a nation of workaholics. Americans work longer hours and take shorter vacations than almost any other developed country on Earth.

In other words, we give people a choice of how to spend their lives. Then we all turn around, send our children to daycare, and spend the first decades of our professional life working late into the night.

I’ve heard many explanations for why Americans are such workaholics. Few of those arguments are convincing. Some have claimed, for example, that a decade of recession has forced America’s hand when it comes to work vs. leisure (what economists call an income effect). According to this rhetoric, as wages stagnate and spouses lose their job, people are working longer and longer hours.

Others claim that work gives people meaning. Working, it is said, is almost a form of leisure.

I don’t buy it. First, I agree that the recession has changed things. Dramatically. But America’s obsession with work has a long history – if you look at the statistics, Americans were working longer hours than Europeans in the 90’s as well.

Likewise, it’s hard to pick up a paper without finding another article telling us how the decline of real manufacturing jobs and the rise of service-sector, information jobs has created a generation of people who feel alienated and disconnected from the product (if any) that their company produces.

Why do we work so much?


Here is what’s actually going on:

I have a simple explanation, and it’s one that you can experiment with yourself to see if it’s convincing (don’t worry, it doesn’t involve telling your boss to do anything unseemly with those TPS Reports). It comes down to this: Our brain has a very difficult time maximizing more than one thing.


Below, I’ve included three examples. In each one, focus on the thought process you go through to maximize happiness.


Let’s start with example 1. Let’s say that you like money. We’ll quantify that as saying that the amount your job pays you every hour gives you a total of five units of happiness (this is completely arbitrary). There are 24 hours in the day, and there is nothing else that makes you happy (not even sleep). So when you decide how much to work, you are faced with the following decision:

H = 5 x W          (where H is your happiness and W is the number of hours you work)

H is less than or equal to 24      (the number of hours in the day)

This is a decision, but it’s an easy one. To maximize happiness, you want to work as much as possible. The day has 24 hours, so you work nonstop. You are happy.


Of course, that’s not how life actually works. On to example 2. You like to work – but you like to sleep as well. Each hour of sleep gives you 3 units of happiness.

H = (5 x W) + (3 x S)        (where S is the number of hours of sleep you get)

H + S is less than or equal to 24

Easy again. The introduction of two activities may have made the thought process a tad bit longer, but you knew that each hour of sleep was not as happiness-inducing as each hour of work. So, again, you didn’t sleep at all. Instead, you worked 24 hours, earned 5 happiness per hour, and ended up with 120 happiness.


Now, let’s make the situation truly realistic (here is the exciting part). Example 3: suppose that, as before, you are choosing between sleep and work. But now suppose that, as is actually the case, your body prefers to not sleep all the time, and not work all the time. You want rest, but you don’t want to sleep in for so long that you get restless. This is what economists call an interaction term. For our intents and purposes, it is simply an extra term at the end of our decision equation:

H = (5 x W) + (3 x S) + (W x S)

H + S is less than or equal to 24

The concept is surprisingly simple: there is a bonus to mixing it up (to see this, notice that if W is 1 and S is 23, then W x S equals 23. But if W is 2 and S is 22, W x S is much larger – 44).

Easy enough right?

If you’re shaking you’re head, you just demonstrated my point. In fact, the subtle difference between solving Example 2 and Example 3 is the difference between high school calculus and college level microeconomics. Even if you had a pen, paper, a calculator, and a solid understanding of LaGrangian multiplers, solving Example 3 would still take you a while. Doing it in your head is an exercise in frustration (the answer, by the way, is 13 hours spent working and 11 hours spent sleeping).


What we just showed:

People are simply not wired to maximize two things at once, especially if those two things feature any higher-level interaction. If you ask someone to earn as much money as possible, they’ll have no problem doing it: they’ll simply buy some Red Bulls and start chugging. But once people are required to juggle two, competing options, the brain throws a fit. Three or more (e.g. raising kids, working, and sleeping)? It’s mathematical challenging. Mentally, it’s virtually impossible. So people simplify.

I believe we work ourselves so hard not because we’ve decided it’s the optimal way to spend our life, but because the mental effort needed to optimize the dozens of choices we have in this country of how to spend our time is not something we are mentally wired to do.

So we drink our Red Bulls and chug away.

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