Photographs of Christopher Alexander’s sketches of the fifteen fundamental geometric properties, for his selection of one sketch for each property

Fifteen photographs of sketches, each one presenting one of the following properties: 1. Levels of Scale; 2. Stong Centers; 3. Boundaries; 4. Alternating Repetition; 5. Positive Space; 6. Good Shape; 7. Local Symmetries; 8. Deep Interlock; 9. Contrast; 10. Gradients; 11. Roughness; 12. Echoes; 13. The Void; 14. Simplicity & Inner Calm; 15. Not-Separateness.