David Parnas Born : February 10, 1941 Browse All Authors Top 15 quotes by David Parnas Copy and paste is a design error. David Parnas funny-inspirational design errors One bad programmer can easily create two new jobs a year. David Parnas jobs two years When someone builds a bridge, he uses engineers who have been certified as knowing what they are doing. Yet when someone builds you a software program, he has no similar certification, even though your safety may be just as dependent upon that software working as it is upon the bridge supporting your weight. David Parnas safety knowing bridges As a rule, software systems do not work well until they have been used, and have failed repeatedly, in real applications. David Parnas learning real insomnia Artificial intelligence has the same relation to intelligence as artificial flowers have to flowers. David Parnas artificial-intelligence flower relation I have found that the reason a lot of people are interested in artificial intelligence is the same reason a lot of people are interested in artificial limbs: they are missing one. David Parnas missing reason people We must not forget that the wheel is reinvented so often because it is a very good idea; I've learned to worry more about the soundness of ideas that were invented only once. David Parnas wheels worry ideas Many spend their time berating practitioners for not applying their method. We all need to disseminate our ideas, but most of our time should be spent applying and improving our methods, not selling them. The best way to sell a mouse trap is to display some trapped mice. David Parnas way ideas needs With software products, it is usual to find that the software has major `bugs' and does not work reliably for some users... The lay public, familiar with only a few incidents of software failure, may regard them as exceptions caused by exceptionally inept programmers. Those of us who are software professionals know better; the most competent programmers in the world cannot avoid such problems. David Parnas bugs may world Complexity is not a goal. I don't want to be remembered as an engineer of complex systems. David Parnas complexity goal want Whenever anyone says, 'theoretically', they really mean, 'not really'. David Parnas mean-girls humorous science There are no standards for computer programmers and no group to certify them. David Parnas standards computer groups Find the simplest model that is not a lie is the key to better software design. David Parnas design keys lying Requirements in mathematical language are no use unless they are easier to read than the code. David Parnas requirements language use My judgment is that research in 'Star Wars' is going to fail, and I believe this so strongly that I'm willing to stake my professional reputation on this. I don't believe anybody is going to build this thing. David Parnas stars war believe
