Question
What is availability heuristic?
Quick Answer
Your sense of cognitive completeness is an illusion. What you can access at any moment is a context-dependent sample of what you actually know — and the sample changes without your awareness.
Example: Ask yourself to list every active commitment you have right now. You'll produce a list that feels fairly complete. It's missing at least 30-40% of the actual items. The items aren't gone — they're in long-term memory — but they're not in your current retrieval set. What's worse: you don't feel the gap. The list feels complete because your brain treats available information as all information.
This concept is part of Perception and Externalization in the How to Think curriculum, which builds the epistemic infrastructure for perception and externalization.
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