Christopher Alexander authored A Pattern Language in 1977 and inspired a movement in software, interface design, and more. Alexander's The Nature of Order: An Essay on the Art of Building and the Nature of the Universe outlines the properties that underlie beauty in art, nature, and great buildings:
- Levels of Scale: A balanced range of sizes is pleasing and beautiful.
- Strong Centers: Good design offers areas of focus or weight.
- Boundaries: Outlines focus attention on the center.
- Alternating Repetition: Repeating various elements creates a sense of order and harmony.
- Positive Space: The background should reinforce rather than detract from the center.
- Good Shape: Simple forms create an intense, powerful center.
- Local Symmetries: Organic, small-scale symmetry works better than precise, overall symmetry.
- Deep Interlock and Ambiguity: Looping, connected elements promote unity and grace.
- Contrast: Unity is achieved with visible opposites.
- Gradients: The proportional use of space and pattern creates harmony.
- Roughness: Texture and imperfections convey uniqueness and life.
- Echoes: Similarities should repeat throughout a design.
- The Void: Empty spaces offer calm and contrast.
- Simplicity and Inner Calm: Use only essentials; avoid extraneous elements.
- Not-Separateness: Designs should be connected and complementary, not egocentric and isolated.