Dave Parnas quotes:

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

As a rule, software systems do not work well until they have been used, and have failed repeatedly, in real applications.

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.

There are no standards for computer programmers and no group to certify them.