Separate facts, assumptions and stories before deciding

The short answer

Write the verified facts first, then label interpretations, assumptions and unknowns separately. A decision can use all four, but confidence should depend on source quality, directness, freshness, independence and whether alternative explanations were tested.

Use the four-column reality check

1. Facts Observations with a traceable source: an event happened, a number was recorded or a person said specific words.
2. Interpretations What the facts may mean, without claiming causality.
3. Assumptions Beliefs that must be true for the plan or explanation to hold.
4. Unknowns Information that could materially change the decision but is not currently available.

Weight evidence, do not merely count it

Three repeated summaries may all originate from the same mistaken source. Direct behavior is often stronger than retrospective explanation; recent evidence may matter more in a changing market; independent evidence reduces correlated error.

Confidence should fall when the claim is causal, the downside is high, the evidence is indirect or the decision is difficult to reverse.

Questions

Are personal reflections facts?

They are facts about what you reported or felt, but causal explanations inside them remain interpretations or assumptions.

What makes a source reliable?

Relevant dimensions include directness, accuracy history, freshness, independence and incentives.

Can I decide with incomplete information?

Yes. Make uncertainty explicit and match the evidence burden to reversibility and downside.