Engineering Change?

January 25, 2009


Because two of my kids – and most of their friends – are engineers.

Henry Petroski in today’s Washington Post:engineering

“We will restore science to its rightful place,” President Obama declared in his inaugural address. That certainly sounds like a worthy goal. But frankly, it has me worried. If we want to “harness the sun and the winds and the soil to fuel our cars and run our factories,” as Obama has decreed, we shouldn’t look to science. What we need is engineering.

To be fair, Obama’s misconception is a common one. Most people who aren’t scientists or engineers seem to think that science and engineering are the same. They’re not. Science seeks to understand the world as it is; only engineering can change it.

That’s not what most high-school teachers or even college professors tell their science students. But the truth is that full scientific understanding isn’t always necessary for technological advancement. Take steam engines: They were pumping water out of mines long before a science of thermodynamics was developed to explain how they worked. The engines were what prompted researchers to look into the nature of steam power in the first place.

This may make me a heretic, but I’ll take the argument a step farther: Science can actually get in the way of technology. In the 19th century, some scientists were convinced that even the largest steamship couldn’t carry enough coal for transatlantic trips. Only when skeptical engineers designed ships that made this supposedly impossible task possible were the naysaying scientists forced to reconsider.

And think about the Wright brothers, who refused to believe that only birds were meant to fly. If Wilbur and Orville had waited for the publication of a sophisticated textbook on aerodynamics, they might never have left their bicycle shop in Dayton for the dunes of Kitty Hawk. Engineering, not science, enabled them to develop propellers that worked in the air the way a ship’s propeller spins through water.

Steamships and flying machines may seem like things of the past, but the ingenuity behind them couldn’t be more relevant today. Some of our greatest energy challenges require engineering breakthroughs, not scientific discoveries. The principles that explain how a battery works, for example, are old news. But a lightweight and cost-effective battery pack with enough juice to power a car over long distances remains an elusive goal.

The same is true of fuel and solar cells. Scientists established long ago that natural processes involving chemicals and sunlight can produce electricity. We need engineers to make the cells lean enough to compete with coal and oil. Science alone is never enough.

The president and his green team — particularly Energy Secretary Steven Chu — appear to understand the urgency of the world’s energy problems. I’m not so convinced that they accept that science, for all its beauty, is not the best place to seek practical fixes. Obama should keep his promise to “restore science to its rightful place” — and put engineering on at least an equal footing.

Henry Petroski is a professor of civil engineering and history at Duke University.