Notes on the synthesis of forms is an awesome book! It really is about systems design in general - the graph based view is the concrete formulation of the fact that elements of the system affect each other amd if these connections are not made explicit in the design process then the components will still be connected - albeit in hidden and accidental ways which will make the system development into a neverending game of whac-a-mole problem fixing.<p>In retrospect this may sound obvious and trivial but taking this simple graph based view of the basis of systems design as the fundamental idea gives concreteness to e.g. lot of software systems practices and unifies them.