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.

The role of a trainer or consultant is to empower the customer, not to make himself indispensable

Perfect reusable components are not obtained at the first shot.

Ask not first what the system does; ask what it does it to!

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

Careful as they may be, developers of Eiffel libraries will always run into cases in which, after releasing a library class, they suddenly experience what in French is called esprit de l'escalier or wit of the staircase: a great thought which unfortunately is an afterthought, like a clever reply that would have stunned all the other dinner guests - if only you had thought of it before walking down the stairs after the party is over.

You can either have software quality or you can have pointer arithmetic, but you cannot have both at the same time.