Henry Petroski Quotes

Science is about knowing; engineering is about doing.

- Henry Petroski

It has been said, by engineers themselves, that given enough money, they can accomplish virtually anything: send men to the moon, dig a tunnel under the English Channel. There's no reason they couldn't likewise devise ways to protect infrastructure from the worst hurricanes, earthquakes and other calamities, natural and manmade.

- Henry Petroski

I was always told that I was good in mathematics, and I guess my grades and standardized test scores supported that. My worst subjects were those that generally involved a lot of reading - English and history. So, having good test scores in math and mediocre ones in reading, I was naturally advised to major in engineering in college.

- Henry Petroski

There's so much written about the Titanic, and it's hard to separate what's fact and what's fiction. My understanding is that the way the Titanic was designed, the emphasis was placed on surviving a head-on collision.

- Henry Petroski

Typically, highway bridges have about 50 years. But over in England, they have iron bridges approaching 250 years. In France, there are Roman aqueducts that are approaching 2,000 years old. So a bridge can last a very long time if it's built properly in the first place and then maintained properly.

- Henry Petroski

Failures are much more dramatic than successes, and people like drama. I think this is why automobile races draw such crowds. People expect spectacular crashes, which we tend to find more interesting than cars just racing around the track. The same is true of bridges, buildings, or any structure or machine.

- Henry Petroski

Successful engineering is all about understanding how things break or fail.

- Henry Petroski

Engineering is achieving function while avoiding failure.

- Henry Petroski

Indeed, an engineer designing a structure is not unlike an artist painting one. Both start with nothing but talent, experience, and inspiration. The fresh piece of paper on the drawing board is as blank as the newly stretched piece of canvas.

- Henry Petroski

We call the fates of the Titanic and the Concordia - as well as those of the space shuttles Challenger and Columbia - 'accidents.' Foreseeing such undesirable events is what engineers are expected to do. However, design trade-offs leave technological systems open to failings once predicted, but later forgotten.

- Henry Petroski

Everything we do is designed, whether we're producing a magazine, a website, or a bridge. Design is really the creative invention that designs everything.

- Henry Petroski

Betting on the success of innovative technologies in the marketplace can carry all the uncertainty and risk that betting on the next card in the deck does at a blackjack table in Las Vegas. There is a factor of randomness that must be factored in, but precisely how to do so is anyone's guess.

- Henry Petroski

As engineers, we were going to be in a position to change the world - not just study it.

- Henry Petroski

We can't simply blame the engineers when things go wrong because, no matter how well they plan, things don't always go according to plan.

- Henry Petroski

The same aspirations to celebrate and uplift the spirit that drove the Egyptians to build the pyramids are still driving us. The things we're doing differ only in magnitude.

- Henry Petroski

Many of the familiar little things that we use every day have typically evolved over a period of time to a state of familiarity. They balance form and function, elegance and economy, success and failure in ways that are not only acceptable, but also admirable.

- Henry Petroski

An over-reliance on past successes is a sure blueprint for future failures.

- Henry Petroski

My first book, 'To Engineer Is Human,' was prompted by nonengineer friends asking me why so many technological accidents and failures were occurring. If engineers knew what they were doing, why did bridges and buildings fall down? It was a question that I had often asked myself, and I had no easy answer.

- Henry Petroski

Successful design is not the achievement of perfection but the minimization and accommodation of imperfection.

- Henry Petroski

Luxury, not necessity, is the mother of invention. Every artifact is somewhat wanting in its function, and that is what drives its evolution.

- Henry Petroski

No design, no matter how common or seemingly insignificant, is without its adamant critics as well as its ardent admirers.

- Henry Petroski

I have always been fascinated by the way things work and how they came to take the form that they did. Writing about these things satisfies my curiosity about the made world while at the same time giving me an opportunity to design a new explanation for the processes that shape it.

- Henry Petroski

Case studies of failure should be made a part of the vocabulary of every engineer so that he or she can recall or recite them when something in a new design or design process is suggestive of what went wrong in the case study.

- Henry Petroski

Because they are so humbled by their creations, engineers are naturally conservative in their expectations of technology. They know that the perfect system is the stuff of science fiction, not of engineering fact, and so everything must be treated with respect.

- Henry Petroski

The definition of 'safe' is not strictly an engineering term; it's a societal term. Does it mean absolutely no loss of life? Does it mean absolutely no contamination with radiation? What exactly does 'safe' mean?

- Henry Petroski

Companies selling a product play down its vulnerability and emphasize its robustness. But only after technology leaves the dock is it really tested. For human operators in control of a supposedly infallible system, complacency and overconfidence can take over, and caution may be thrown to the wind.

- Henry Petroski

I relax by looking at things and reading about things. Even the simplest thing can reveal a great deal about the world around us. It relaxes me greatly to sit back with my feet up and look around my study at the everyday things that surround me.

- Henry Petroski

The space shuttle was designed, at least in part, to broaden our knowledge of the universe. To scientists, the vehicle was a tool; to engineers, it was their creation.

- Henry Petroski

For as long as I can remember, I have been fascinated by things large and small. I wanted to know what made my watch tick, my radio play, and my house stand. I wanted to know who invented the bottle cap and who designed the bridge. I guess from early on I wanted to be an engineer.

- Henry Petroski

The paradox is that when we model future designs on past successes, we are inviting failure down the line; when we take into account past failures and anticipate potential new ways in which failure can occur, we are more likely to produce successful designs.

- Henry Petroski

Many new technologies come with a promise to change the world, but the world refuses to cooperate.

- Henry Petroski

I employ case studies of failure into my courses, emphasizing that they teach us much more than studies of success. It is not that success stories cannot serve as models of good design or as exemplars of creative engineering. They can do that, but they cannot teach us how close to failure they are.

- Henry Petroski

Too much redesign has to do more with fad and fashion than with fitness and function. It is change for the sake of change. Such redesign is not only unnecessary, it is all too often also retrogressive, leading to things that work less effectively than those they were designed to replace.

- Henry Petroski

Any design, whether it's for a ship or an airplane, must be done in anticipation of potential failures.

- Henry Petroski

It is really want, rather than need, that drives the process of technological evolution.

- Henry Petroski

All conventional wisdom has an element of truth to it, but good design requires more than an element of truth - it requires an ensemble of correct assumptions and valid calculations.

- Henry Petroski

You can almost say that a design error is a human error because, after all, it's we humans who do the designing.

- Henry Petroski

A common misconception about how things such as space shuttles come to be is that engineers simply apply the theories and equations of science. But this cannot be done until the new thing-to-be is conceived in the engineer's mind's eye. Rather than following from science, engineered things lead it.

- Henry Petroski

Although engineers want always to make everything better, they cannot make anything perfect. This basic characteristic flaw of the products of the profession's practitioners is what drives change and makes achievement a process rather than simply a goal.

- Henry Petroski

I'm a firm believer that no matter how small an object is, you can find interesting things out about it and its history.

- Henry Petroski

If I could go upstairs and write every day, I would be happy. I don't need recreation.

- Henry Petroski

It seems to be a law of design that for every advantage introduced through redesign, there is an accompanying unintended disadvantage.

- Henry Petroski

As long as there are things to wonder about, there are stories to be written about them. That makes me happy, because writing about things seems to be my thing.

- Henry Petroski

Relying on nothing but scientific knowledge to produce an engineering solution is to invite frustration at best and failure at worst.

- Henry Petroski

Because every design must satisfy competing objectives, there necessarily has to be compromise among, if not the complete exclusion of, some of those objectives, in order to meet what are considered the more important of them.

- Henry Petroski

Failure is central to engineering. Every single calculation that an engineer makes is a failure calculation. Successful engineering is all about understanding how things break or fail.

- Henry Petroski

I emphasize that virtually every engineering calculation is ultimately a failure calculation, because without a failure criterion against which to measure the calculated result, it is a meaningless number.

- Henry Petroski

Read and write with a sensitive ear. The craft of writing is very important. Practice the craft.

- Henry Petroski

Design is nothing if not decision making.

- Henry Petroski