Proietti publishes her new book, Hans van der Laan: Instruments of Thought. Proportion, Architecture, Analogy, co-authored with Kees den Biesen. We reexamine the critical role of proportion in architecture, starting from Van der Laan’s Plastic Number theory. We explore Van der Laan’s three key intellectual strategies, or “instruments of thought”— the search for a theory of architecture; the establishment of a three-dimensional system of proportions named Plastic Number; and analogy as the mainspring of human thinking—urging a deeper understanding of the role of proportion in architecture. We aim to reintegrate playful creativity and intellectual exploration into architectural practice and education, encouraging a renewed appreciation of how we perceive proportion and how proportion affects our experience of the built environment.