Diverge Before You Converge
Hold generation and evaluation in strictly separated phases; never allow convergent thinking to enter a divergent phase. Phase transitions must be named, explicit, and mutually agreed — never a silent drift.
- Osborn (1953) and IDEO's seven brainstorming rules both encode "defer judgment" as the primary law of ideation; six decades of replication have confirmed it as the highest-leverage single rule
- The Default Mode Network (generative) and Executive Control Network (evaluative) are in active tension (Beaty et al., 2016, Trends in Cognitive Sciences); triggering evaluation during generation cancels the generative state at the neurological level
- Diehl & Stroebe (1987, 1991, JPSP): even the possibility of being overheard evaluating suppresses generation — phase-gating is the structural intervention that eliminates this
- The Double Diamond (Design Council, 2005) and Six Thinking Hats (de Bono, 1985) both make diverge/converge phase separation their core structural mechanism
- Announce phases explicitly ("We're diverging now — no evaluation yet") and treat a phase shift as a joint decision: never shift unilaterally