Incorrect documentation is often worse than no documentation.

Writing a class without its contract would be similar to producing an engineering component (electrical circuit, VLSI (Very Large Scale Integration) chip, bridge, engine...) without a spec. No professional engineer would even consider the idea.

Constants are widely known for the detestable practice of changing their values; we should prepare ourselves against the consequences of such fickleness

I think Smalltalk is inappropriate for serious industrial developments. After all, run time is a little late to find out whether you have a landing gear.

I have always felt sympathy towards the biologists who accept to debate creationists. Now I also understand them better; one can fight opinions, not articles of faith.

Incorrect documentation is often worse than no documentation.

Correctness is clearly the prime quality. If a system does not do what it is supposed to do, then everything else about it matters little.