How many times have you thrown your Saturday morning plans out the window in favor of an extra two hours of sleep? How many New Year's resolutions do you carry over year to year? How many brilliant ideas never stand a fighting chance because you're too absorbed by the online and flat-screen worlds?

The feeble battle cry "I'll get around to it" is a phrase our ancestors likely never uttered. Their focus was survival in the here and now. Our focus is how to make the here and now as comfortable as possible. And because our basic needs are relatively easily met, we have the luxury—and burden—of fretting, , and procrastinating about future actions, while doing very little.

In the grand scheme of things, we're all members of the leisure class now. No matter how hard you work (and I'm sure you work hard), you've likely got it better than any generation in the history of mankind.

For most of human existence, resources were scarce and unpredictable, so it behooved us to conserve energy as much as possible. External motivators were powerful and compelling: Starvation and predation were constant threats; days and nights alternated between searing sunlight and freezing darkness. Because it was so critical for our nomadic forebears to conserve energy, we evolved to expend minimal effort when we can get away with doing so.

Today our lot is reversed: We have abundant sources of energy and few directly compelling motivators. Most of us are not parched or hunted by homicidal predators. Enter ego concerns, predinner martinis, window-shopping, and the mixed blessing of long-term planning.

Our ancestors encountered little delay between desire and action: Feeling thirsty meant looking for water, feeling hungry meant looking for food, and feeling amorous meant looking for mates. Our behavior required little or no .

The emotions that helped our ancestors survive were born out of short-term exigency. There was no point thinking long-term in a world without medicine, banks, or even refrigeration. That's not to say they couldn't dream big. But it's not hard to imagine their dreams getting interrupted by requirements of daily survival.

As Kalman Glantz, a psychotherapist and the coauthor of Exiles From Eden, points out, laziness emerged only when planning for the future became possible. "Once there was some reason to continue working even though one's immediate needs were satisfied, some people turned out to be more future-oriented than others. Some people continued to work when they weren't hungry or cold or thirsty. And those people called others lazy."

Many of us feel oppressed by long-term goals that do not bear directly on survival or status—they gnaw at us and distract from our daily enjoyment. Sticking to a workout regimen, jump-starting that screenplay, and transferring vinyl to digital are all easier planned than done. That's because, in general, we're keenly responsive to immediate stimulation and to present-moment distractions and not to iffy future plans. Instead of recognizing that it is fundamentally ingrained in our nature to discount the amorphous future, we lambaste ourselves over what we "should" be doing.

Laziness by definition is not uncomfortable—it is simply an unwillingness to expend energy. But laziness in an environment where we could be highly productive is a recipe for discomfort.

Our evolutionarily novel environment allows for grandiose plans and dreams, but these very opportunities can feel overwhelming. Once we've generated a goal, we believe that we've got to do something about it. We're torn between competing desires: I want to accomplish this idealized plan, but it must not be too hard. In fact, I need it to be easy.

That's where comes in. We put off a task because we think it is too difficult; our is to fool ourselves into thinking we'll do it tomorrow. Some psychologists even allege that procrastination has been deemed a problem only since the Industrial Revolution, when scheduling demands drastically increased.

Because we evolved with a focus on immediate returns, any behavior that is not instantly rewarding is aversive. Impulsivity was useful for most of human prehistory, because an environment without schedules, snail mail, and quarterly earnings offered instant concrete feedback about one's actions.

Today, impulsivity is strongly associated with procrastination. As Piers Steel, a behavioral scientist at the University of Calgary, points out, we'd rather do that which is promptly rewarding, like playing Nintendo, than study for an exam that is months away.

Since by definition we cannot get immediate feedback about the future, we can easily lose in our ability to perform a given task that lies ahead, and this becomes a recipe for avoidance and procrastination. We imagine that working toward a long-term goal will be nightmarishly painful and downright unbearable. The reality is that it won't be too bad once we're in the groove (say, after a solid 15 minutes of work).

But 15 minutes of aversive effort is very novel for humans used to immediate feedback. Our tendency toward inertia and procrastination causes us to tell ourselves, "It will be too hard to start working on a grand project, so I'll wait until I feel like it."

Accomplishing practically anything today means overcoming the need for instant gratification—and questioning the idea that a task will be excessively painful. The rewards of getting what you want in the long run make the present-moment hassles worth enduring. Of course, you risk an infinite regress in getting lazy about fighting laziness. Not to worry—you can start work at any time.

How to Fight Inertia

Instant reward is the default setting of the brain, but we like ourselves better when we tackle unpleasant tasks.