What is bisociation Koestler?

Bisociation Koestler is a concept in personal epistemology: Many innovations come from resolving what seemed like irreconcilable contradictions.

Example: Genrich Altshuller analyzed 200,000 patents and discovered that breakthrough inventions — the top 5% — all shared one pattern: they resolved a contradiction that everyone else had accepted as a trade-off. A submarine hull must be strong (to withstand pressure) AND lightweight (to be maneuverable). Rather than choosing one, the inventor found a solution where both requirements are satisfied simultaneously. The contradiction was the starting point, not the obstacle.

This concept is part of Phase 19 (Contradiction Resolution) in the How to Think curriculum, which builds the epistemic infrastructure for contradiction resolution.