Question
What is DRY principle?
Quick Answer
When you write the same idea twice you have not yet named the pattern they share.
Example: You have three notes in your knowledge system about staying calm under pressure — one filed under 'leadership,' one under 'parenting,' and one under 'difficult conversations.' They use different words but describe the same cognitive move: pause, observe your emotional state, choose your response deliberately. The duplication signals a missing abstraction. Extract the shared pattern — 'stimulus-response decoupling' — name it, give it one canonical note, and link the three contexts to it. Now you have one idea that serves three domains instead of three scattered copies that will drift apart.
This concept is part of Atomicity and Decomposition in the How to Think curriculum.
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Go beyond the answer
This topic is part of The Signal Cascade — a guided sequence of 20 lessons.
After completing this path you will run a working signal cascade: a decision-anchored definition of signal (a difference that makes a difference to a decision you own), gates tuned by position (recall at the bottom, precision at the top), knowledge stored as six-field self-validating artifacts, contradictions surfaced at save time, AI output supervised by exception with alarm-audited gates, verification debt tracked and paid down, and sessions run as thin slices with one question, a bounded working set, and an exit artifact.
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