Google self-driving car. Steve Jurvetson, WikiMedia Commons. 

In 1906, future President Woodrow Wilson said the automobile offered "a picture of the arrogance of wealth." It was, in his mind, an ostentatious luxury available to only a few. The personal computer was treated similarly seven decades later. A 1984 article complained that email "reduces human contact and the pleasantries that accompany phone calls."

New technology can be not only written off but scorned by those who don't understand it and view it as a crutch for laziness.

Something similar may be occurring right now with the blossoming technology of self-driving cars.

Tesla (TSLA -1.06%) aims to develop a car capable of driving itself 90% of the time within three years. Google (GOOGL 0.69%) is developing a fleet of self-driving cars that have "logged hundreds of thousands of test miles without incident," according to The Wall Street Journal. Nissan plans to sell "affordable" self-driving vehicles by 2020. 

What good is a self-driving car? Its obvious benefit is the ability to generate free time during your commute. No more staring at traffic. Feel free to take a nap, check your Facebook, or, by all means, play Candy Crush on your way to work.

If your imagination stops there, self-driving cars may look like another step toward laziness and disengagement. Sure, it might cut down on auto accidents and traffic. But we still have to drive to work; we just get to sit idly by as computers chauffeur us along. It's like something out of the movie "WALL-E". 

But become a little more imaginative, and you can see how a self-driving car could do so much more. 

Imagine it's four in the afternoon. You are swamped at work and realize you have no food at home for dinner. Instead of leaving early for a trip to the grocery store, you pull up a Safeway app on your phone and order what you need. While you go about your day, your self-driving car leaves your office's parking garage and drives itself to Safeway. A Safeway attendant scans its license plate, downloads your order, retrieves the items from the store and loads them into your trunk. Your self-driving car returns to work and parks itself. It's waiting for you with a trunk full of groceries whenever you're ready. Maybe you do the same to pick up your dry cleaning, take your kids to school, fill up the gas tank, drop off a package, change your oil, or buy a new pair of jeans. Anything that requires you driving somewhere to pick something up can be automated. The car does it for you.

We already have versions of this. Nearly anything can be ordered online, and Amazon even delivers groceries to your door in some cities. But both are limited by speed on the customer side, and cost on the company side. I don't want to wait three days for my toothpaste to be shipped; I need it tonight. And it's not cost-efficient or logistically feasible for local stores to provide same-day delivery on small, cheap items. Self-driving cars solve both problems. Companies don't need to come to us; we'll come to you. Or, rather, our self-driving cars will come to you while we go about our day.

How much time will this save you? One hour a week? Two to three? More? I don't know the answer; no one does. But however much time it saves you is a net gain -- not just to play games while sitting in a commute you already have, but more time to spend with your family, work, start a new project, whatever. It's that kind of productivity growth that fuels long-term economic growth. And self-driving cars could give us the biggest boost we've seen in years.

This is all speculation, if not dreaming. But too many Americans look around and ask where future economic growth will come from, worried that the low-hanging fruit is gone. Like those who couldn't understand the car or the computer, they'll be proven wrong.