Systems Thinking — From SE to STPA¶
Applying Systems Engineering Decomposition, Product Line Thinking, and STPA to Social and Technical Systems¶
A place to start
In 1975, Kodak built the world's first digital camera — and buried it. Twenty years later, digital photography destroyed the company that invented it. The engineers were excellent. The technology was real. The failure was structural: the organisation was wired to protect film revenues, and it reliably smothered anything that threatened them. No personnel change could have fixed it. The design had to change. Most institutional failures look like this. The Introduction develops this argument through several cases before any framework or equation appears.
This book explores a single, powerful idea: the tools we use to engineer safe aircraft and reliable software apply with surprising precision to human institutions — political regimes, religions, corporations, families, and development methodologies.
We use three frameworks, layered on top of each other:
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The Five-Level SE Hierarchy — decompose any system into Goals → Requirements → Functions → Logical Architecture → Physical Implementation, with full traceability.
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Product Line Thinking — compare systems by identifying their shared platform (what's common) and their variation points (where they diverge), then study which elements can be reused across system types.
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STPA (System-Theoretic Process Analysis) — model the system as a hierarchical control structure and systematically identify unsafe control actions that produce outcomes opposite to the system's stated goals.
Structure¶
The book is organized in four parts:
| Focus | |
|---|---|
| Introduction | Why structural analysis beats moral exhortation — argued through concrete cases |
| Part I — Foundations | What is a system? The three frameworks: SE hierarchy, product lines, STPA |
| Part II — Social Systems | Ten social systems decomposed and compared |
| Part III — Development Frameworks | Waterfall, Scrum, Kanban, DevOps, and others — analysed as a product family |
| Part IV — STPA Applied | STPA applied to religion and other social systems |
The Core Insight¶
Social systems look more different from each other than they actually are. A kingdom and a republic, a church and a corporation, a family and a Verein — these seem like categorically different things. But when decomposed through a rigorous systems engineering hierarchy, they reveal a shared platform of functional slots, and they differ primarily at a small number of well-defined variation points.
Product line thinking does not reduce human institutions to interchangeable parts. It does the opposite: it makes the genuine differences visible by stripping away the illusion that everything is different.
And STPA reveals that the most harmful outcomes of social systems are not random malfunctions but predictable consequences of their control architecture — consequences that can be addressed through architectural redesign, not just moral exhortation.