What does it mean that compound ideas hide dependencies?

An idea that looks like one thing is often several things fused together, each carrying unstated assumptions that silently constrain what you can do with it.

Example: You believe 'we should expand into the European market.' That single sentence bundles at least four assumptions: (1) there is demand in Europe for what you sell, (2) your product can be localized without fundamental redesign, (3) you have or can acquire the operational capacity to serve European customers, and (4) the regulatory environment permits your business model. If any one of these is wrong, the entire compound idea collapses — but you won't know which part failed because you never separated them.

Try this: Take one belief you currently hold about your work, career, or a project — something you'd state as a single sentence. Write it down. Now decompose it: list every assumption that must be true for that sentence to hold. Aim for at least four. For each assumption, ask: 'Have I actually tested this, or am I treating it as given?' Circle the untested ones. You've just mapped the hidden dependencies in a compound idea.