The French aviator, aircraft designer and author Antoine de Saint-Exupéry, probably best known for his classic children’s book The Little Prince:
…Perfection is finally attained not when there is no longer anything to add, but when there is no longer anything to take away….
The quote in context, from his book Wind, Sand and Stars:
Have you looked at a modern airplane? Have you followed from year to year the evolution of its lines? Have you ever thought, not only about the airplane but about whatever man builds, that all of man’s industrial efforts, all his computations and calculations, all the nights spent over working draughts and blueprints, invariably culminate in the production of a thing whose sole and guiding principle is the ultimate principle of simplicity?
It is as if there were a natural law which ordained that to achieve this end, to refine the curve of a piece of furniture, or a ship’s keel, or the fuselage of an airplane, until gradually it partakes of the elementary purity of the curve of a human breast or shoulder, there must be the experimentation of several generations of craftsmen. In anything at all, perfection is finally attained not when there is no longer anything to add, but when there is no longer anything to take away, when a body has been stripped down to its nakedness.