In his own words · Circle of competence

“One skill is knowing the edge of your own competency. It's not a competency if you don't know the edge of it. And Warren and I are better at tuning out the standard stupidities. We've left a lot of more talented and diligent people in the dust, just by working hard at eliminating standard error.”

— Charlie Munger · Stanford Lawyer magazine, Spring 2009 (Issue 80), "Q&A: Legal Matters with Charles T. Munger" · 2009

Verified. Sourced to Stanford Lawyer magazine, Spring 2009 (Issue 80), "Q&A: Legal Matters with Charles T. Munger" · 2009.

More Munger on Circle of competence

“Knowing what you don't know is more useful than being brilliant.”

Attributed to Munger · as recalled

Captures his oft-repeated stance on the limits of competence; widely cited, exact occasion not pinned to one recording.

“We have three baskets for investing: yes, no, and too tough to understand.”

Attributed to Munger; Berkshire/Wesco meetings · as recalled · where he said it ↗

Frequently quoted from the Berkshire and Wesco meetings; wording varies.

“If something is too hard, we move on to something else. What could be simpler than that?”

Berkshire Hathaway annual meeting · as recalled · where he said it ↗

“Whatever you think you know about technology, I think I know less.”

Berkshire Hathaway annual meeting, 1998 (morning session) · 1998 · where he said it ↗