Necessity may well be called the mother of invention but calamity is the test of integrity.

Calamity is the test of integrity.

Necessity... the mother of invention.

They say that necessity is the mother of invention, and when the necessity is survival she can be one mean mother, but it's her child invention that's the real dangerous one.

If necessity is the mother of invention, then dissatisfaction must be its father.

Necessity, they say, is the mother of invention, but fear, too, is not barren of ingenious suggestions.