Exponential Information Decay
Unrehearsed information decays exponentially, losing approximately 42% within 20 minutes and ~67% within 24 hours; this decay rate is a fixed property of human memory architecture.
Ebbinghaus (1885) first measured the exponential decay of unrehearsed memory. Murre & Dros (2015) replicated the finding 130 years later with near-identical curves.
The steepest drop occurs in the first 20 minutes — nearly half the signal degrades before you have left the room. This is not a failure of attention or effort; it is the default behavior of human memory when no active rehearsal or externalization intervenes.
This axiom grounds every urgency claim about capture latency. Combined with Working Memory Capacity Limit (capacity limit) and Open-Loop Cognitive Cost (Zeigarnik) (Zeigarnik persistence), it establishes that the window for preserving a thought is measured in minutes, not hours.
Source Lessons
Uncaptured thoughts decay in seconds
Your most novel thinking arrives as fleeting signals. Without a capture practice, you are systematically destroying your own cognitive raw material.
Every thought has a shelf life
Not all thoughts decay at the same rate. A fleeting architectural insight has minutes before it degrades beyond recovery. A stable reference fact has weeks. Treating every thought with the same urgency — or the same patience — guarantees you lose the wrong ones.
Raw capture beats perfect capture
A rough note you actually make is infinitely more valuable than a polished note you do not.
Review completes the capture loop
Captured thoughts that are never reviewed are effectively still lost. The capture habit preserves raw material; the review habit transforms it into usable knowledge. Without review, your capture system becomes a graveyard of good intentions.
Perception is the foundation of all epistemic work
Every system you build for clear thinking, aligned action, and self-correction rests on a single prerequisite: your ability to notice what is happening — in your mind, in your environment, in the gap between them — and externalize it before it disappears.