These are 3 Circle of Competence principles distilled from Ray Dalio's writing and public remarks. Use them as a decision checkpoint: translate each rule into a yes/no test, write what evidence would change your mind, and set a review date before you act. When a rule feels vague, open the full principle page and capture the driver you can verify (cash flows, leverage, incentives, competitive edge). This is educational, not investment advice—double-check primary sources and fit every rule to your time horizon, risk budget, and constraints.
"The biggest mistake investors make is to believe that what happened in the recent past is likely to persist. Being open-minded about what you don't know is the key."
Intellectual humility about unknowns is essential.
Read Full Analysis →"Don't let your ego barrier or blind spot barrier prevent you from seeing things as they really are. Be radically open-minded."
Overcome ego to see reality clearly.
Read Full Analysis →"Not all opinions are equally valuable. Weigh the opinions of believable people more heavily — those who have repeatedly succeeded at the thing in question."
Weight opinions by the track record of the person.
Read Full Analysis →Use this page as a workflow, not a collection of quotes. Pick 3–5 principles, translate each into a concrete check, and review your decisions on a fixed cadence. These are educational guardrails—always verify facts and match them to your own constraints.
Rehearse a scenario decision → ·Run a weekly toolkit → ·Browse all principles →
Dalio is known for developing the "All Weather" portfolio strategy, designed to perform well across all economic environments, and pioneering risk parity investing. His systematic, principles-based approach to investing and management has been highly influenti…
Ray Dalio has 3 key principles on circle of competence. The most important one is "Know What You Don't Know" — The biggest mistake investors make is to believe that what happened in the recent past is likely to persist.
Ray Dalio applies circle of competence through several key principles including "Know What You Don't Know" and "Radical Open-Mindedness". These principles guide practical investment decisions and have been tested across decades of market cycles.
Ray Dalio's approach to circle of competence is distinguished by a focus on long-term thinking and fundamental analysis. With 3 specific principles in this area, Ray Dalio provides a comprehensive framework that investors at any level can study and apply to improve their decision-making.
Treat each principle as a hypothesis. Write the evidence you would need, collect it from primary sources when possible (filings, letters, transcripts), and note what would invalidate the conclusion. If you can’t define inputs and triggers, you’re not applying the rule—you’re quoting it.
Pick a cadence you can sustain (weekly or monthly) and review process signals first: whether you followed your checklist, respected your boundaries, and documented assumptions. Only then look at outcomes. The goal is fewer low-quality decisions, not perfect prediction.
