Separate facts from assumptions explicitly

Sort what you actually know from what you’re assuming, in two visible columns.

Why it works

Facts and assumptions blur together in the head, so assumptions get treated as constraints they are not. Externalizing the split into two explicit lists works by making the assumptions visible and therefore challengeable; an assumption you can see is one you can test or drop. Visibility is what turns a hidden constraint into a choice.

How to do it

1. Draw two columns: “Verified facts” and “Assumptions I’m making.”
2. Force every belief into one column; if you can’t prove it, it’s an assumption.
3. Attack the assumption column — which ones, if false, would change everything?

Evidence

A practical externalization technique consistent with research on how offloading reasoning to external representations reduces cognitive load and surfaces hidden premises. Mechanistic. Larkin and Simon (1987) show why an external diagram outperforms a mental one — it makes the relevant elements directly locatable rather than held in the head — which is the same lever the two-column split pulls; Risko and Gilbert (2016) frame that move as cognitive offloading. (mechanistic)

Offloading research is general; the specific two-column fact/assumption split is a heuristic built on it, not a studied protocol.

Sources

• Research on external representation / cognitive offloading in reasoning and problem-solving
• Risko, E. F., & Gilbert, S. J. (2016). Cognitive offloading. Trends in Cognitive Sciences, 20(9), 676–688.
• Larkin, J. H., & Simon, H. A. (1987). Why a diagram is (sometimes) worth ten thousand words. Cognitive Science, 11(1), 65–100.

Common mistake

Filing assumptions in the “facts” column because they feel certain. The whole value is in being ruthless about what truly belongs as fact.