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Ebbinghaus Forgetting Curve

learningmemoryforgetting-curvecognitive-science

Ebbinghaus Forgetting Curve

The empirical observation, originally from Hermann Ebbinghaus's 1880s self-experiments, that retention of new information decays steeply and fast without reinforcement.

The headline figure quoted in How To Learn Anything So Fast (theMITmonk):

Roughly 70% of new information is gone within 24 hours.

The shape of the curve

Decay is steepest in the first hours, then flattens. Each well-timed review bends the curve — retention after each successful retrieval decays more slowly than before. This is the mechanism that makes Spaced Repetition work: reviews are scheduled near the point where the curve hits the threshold, not before.

Reframe: forgetting as a feature

The MITmonk's framing: the brain isn't broken when it forgets — it's doing exactly what evolution shaped it to do, discard what isn't repeated. The implication is design-level rather than corrective: don't fight forgetting; schedule around it.

Tooling that operationalizes this

  • Remnote — automatic scheduling of review intervals
  • Anki, SuperMemo (referenced lineage; not yet in this wiki)
  • Manual: calendar reminders for "review X in 1d / 3d / 7d / 21d"

Sources