Strong opinions, weakly held.

Paul Saffo, a technology forecaster associated with Silicon Valley and the Institute for the Future, is widely credited with popularizing the maxim “strong opinions, weakly held” as a norm for thinking and debate in fast-changing, uncertain domains. The phrase circulates especially in entrepreneurial and research settings where decisions must be made with incomplete information and then revised quickly as evidence arrives. It is typically invoked as advice about intellectual posture: commit to a clear hypothesis or point of view so you can act and argue productively, but remain ready to abandon or update that view without ego when new data contradicts it. The quote’s prominence owes much to repeated attribution in talks, interviews, and professional culture rather than a single canonical publication.

Saffo’s aphorism captures a stance often recommended in forecasting, strategy, and intellectual inquiry: commit to a clear, testable view of the world (“strong opinions”) while remaining ready to revise it quickly when evidence changes (“weakly held”). The phrase argues against both timidity (no opinion, no decision) and dogmatism (opinions held as identity rather than hypothesis). It implies that good judgment is iterative: you act on the best available model, but you treat that model as provisional. In practice, it encourages decisive action paired with humility, curiosity, and rapid learning—especially in uncertain, fast-changing environments.

“Have strong opinions, weakly held.”
“Strong opinions, loosely held.”