Top 11 Quotes & Sayings by David Parnas

Requirements in mathematical language are no use unless they are easier to read than the code.

Artificial intelligence has the same relation to intelligence as artificial flowers have to flowers.

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.

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.

Find the simplest model that is not a lie is the key to better software design.

Complexity is not a goal. I don't want to be remembered as an engineer of complex systems.

Copy and paste is a design error.

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.

One bad programmer can easily create two new jobs a year.

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.

Whenever anyone says, 'theoretically', they really mean, 'not really'.