Separate divergence from convergence sessions

Keep idea generation and idea selection in separate sittings — never mix the modes.

Why it works

Evaluation and generation use different cognitive states: generation benefits from loose, associative thinking; evaluation requires critical, comparative thinking. Running them simultaneously means neither runs well — the evaluative voice prunes ideas before they fully form, while premature commitment prevents the generative pass from opening up.

How to do it

1. Schedule two separate sessions: one explicitly labeled "generate only," one labeled "select only."
2. In the generate session, write down everything without rating or crossing anything out.
3. In the select session, work from the list — don’t add new options, just choose.

Evidence

The principle of separating divergent and convergent phases is consistent with dual-process accounts of cognition and with the core finding that mixed evaluation-and-generation hurts both quantity and quality of ideas. Parnes & Meadow (1959) gave the phase separation empirical footing: "defer judgment" instructions that hold evaluation out of the generation pass produced more good-quality ideas than concurrent judging. (mechanistic)

The specific two-session format is a practitioner heuristic; the underlying cognitive case for mode separation is theoretical but well grounded.

Sources

• Parnes, S. J., & Meadow, A. (1959). Effects of "brainstorming" instructions on creative problem-solving by trained and untrained subjects. Journal of Educational Psychology, 50(4), 171-176.

Common mistake

Treating the generate session as "done" too quickly — a truly open diverge phase feels uncomfortably unresolved. Stopping when it feels messy is stopping too early.