The Vignelli Canon
Vignelli distilled fifty years of design practice — the New York subway map, American Airlines identity, Knoll furniture, Bloomingdale's bags — into a booklet of principles that reads like a set of commandments delivered with warmth. The Canon covers both "intangibles" (semantics, syntactics, pragmatics, discipline, appropriateness, ambiguity, design is one) and "tangibles" (paper sizes, grids, typefaces, color, layouts) with the economy of someone who has no time left for unnecessary words. He published it as a free PDF before he died, which is itself a design decision consistent with the book's argument that good design serves, not hoards. The constraint is the point: Vignelli used five typefaces his entire career and argued that limitation produces clarity. For anyone building digital products, the lesson is the same — the power comes from what you refuse to do.