Henry Petroski

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

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

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

“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 - E...”

“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....”

“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 th...”

“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 mean...”

“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.”

“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.”

“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 ex...”

“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 sur...”

“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 exa...”

“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 in...”

“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, n...”

“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 suppo...”

“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.”

“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...”

“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...”

“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 co...”

“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 ret...”