The investment journal: a defense against selective memory

A written decision record improves learning because it preserves the information and assumptions available before the outcome was known.

Memory tends to protect the reasons we were right and blur the reasons we were wrong.

Every cycle creates a new narrative. A dated record separates what was knowable from what became obvious later.

Record the liquidity, credit and positioning evidence that informed the decision at the time.

A consistent journal makes recurring errors and strengths easier to identify.

The feedback loop becomes shorter and decision quality compounds across cycles.

The journal becomes a narrative exercise that rationalizes decisions instead of testing them.

The process is qualitative; its value comes from repeated, honest review rather than a single score.

Scheduled reviews, material changes in evidence and clearly defined invalidation points.

Editing the original thesis after the fact or reviewing only successful decisions.

The process fails when records do not include risks, contrary evidence and the conditions that would change the view.

Write the thesis, scenarios, risk and invalidation before committing capital.

Confirmed as an ongoing process principle. Both successful and unsuccessful ideas should remain visible.