>> a pattern language
A Pattern Language · Christopher Alexander · 1977 · Oxford University Press
253 patterns. Each one names something that works. Not rules — observations. The book describes the built world at the level of felt experience, not architectural abstraction.
The patterns nest: cities contain neighborhoods, neighborhoods contain buildings, buildings contain rooms. Each scale has its own logic. Alexander's claim is that the patterns are not invented — they are discovered. They exist wherever people feel at home.
The section on light is the one that stays. Every room should have light on two sides of it. A room lit from one direction produces glare and flat shadow. Two directions produces depth. The eye relaxes. It seems obvious once stated. It isn't obvious until then.
The book was adopted by software engineers in the 1990s as the basis for design patterns. That translation captured the structure but lost something — the insistence that the pattern must feel right, not just function correctly. Alexander always meant the body, not only the system.