Quote Origin: An Expert Is a Person Who Has Made All the Mistakes Which Can Be Made in a Very Narrow Field

Niels Bohr? Edward Teller? Werner Heisenberg? W. P. Northrup? Benjamin Stolberg? Harry M. Meacham? Eugene Kane? Anonymous?

Question for Quote Investigator: Expertise is often acquired by learning from a series of errors. Here are three pertinent statements whose meanings diverge. The similarities suggest that these remarks still belong in the same family:

(1) An expert is a person who has found out by his own painful experience all the mistakes that one can make in a very narrow field.

(2) An expert is someone who knows some of the worst mistakes that can be made in his subject and how to avoid them.

(3) I’ve made all the mistakes that are possible. The net result of that should be expert.

The first item has been attributed to nuclear scientist Edward Teller and Danish physicist Niels Bohr. The second item has been credited to German theoretical physicist Werner Heisenberg. Would you please explore this topic?

Reply from Quote Investigator: The earliest match for the first item known to QI appeared in “LIFE” magazine in 1954 within a profile of Edward Teller who ascribed an instance to Niels Bohr. Boldface added to excerpts by QI:1

But mistakes do not inhibit him. He likes to quote the dictum of Niels Bohr, the great Danish physicist, that, “An expert is a person who has found out by his own painful experience all the mistakes that one can make in a very narrow field.”

The earliest match for the second item known to QI appeared in a 1952 essay by Werner Heisenberg titled “Positivismus, Metaphysik und Religion” (“Positivism, Metaphysics and Religion”). Here is an excerpt translated into English:2

Many people will tell you that an expert is someone who knows a great deal about his subject. To this I would object that no one can ever know very much about any subject. I would much prefer the following definition: an expert is someone who knows some of the worst mistakes that can be made in his subject, and how to avoid them.

The earliest match for this general family of sayings located by QI appeared in “The Chicago Medical Recorder” in 1904 within an article by Professor of Pediatrics W. P. Northrup of New York University who had become adept at diagnosing and treating pneumonia in infants:3

My one admirer kindly spoke of me, he being in an amiable mood, as an expert in this diagnosis. “Yes,” I agreed, which took him aback, “I’ve made all the mistakes that are possible.” The net result of that should be expert.

Below are additional selected citations in chronological order.

In 1913 a thematically related quip expressing a contrasting viewpoint appeared in the “Evening Kansan-Republican” of Newton, Kansas which acknowledged the “Atchison Globe” newspaper:4

Experts make nearly all the big mistakes.

In 1916 the periodical “American Lumberman” of Chicago, Illinois published the following:5

A man of ordinary intelligence and education can fix up his own system of statistics that will do pretty well. The only reason in the world for using a system that an expert has worked out is that the expert has already made all the mistakes an inexperienced person will make and has gotten them over with, like the measles. He has his system worked out to be simple, easily kept and yielding the most valuable information.

In 1938 the eleventh edition of “Bartlett’s Familiar Quotations” included an entry for a thematically related quip criticizing experts:6

An expert is a person who avoids the small errors as he sweeps on to the grand fallacy. — Benjamin Stolberg [1891- ]

In 1939 “The Boys’ Book of Photography” by Edwin Way Teale contained a chapter about common mistakes which included the following passage:7

Don’t feel humiliated if you fall into these pitfalls. Almost every amateur does — and the professionals did. The crack cameraman is only an ex-beginner who has made all the mistakes and has profited from them!

In 1952 Werner Heisenberg penned a relevant statement in German which has been translated into English as follows as shown previously:

I would much prefer the following definition: an expert is someone who knows some of the worst mistakes that can be made in his subject, and how to avoid them.

In September 1954 Edward Teller credited Niels Bohr with the saying under examination as mentioned previously:

He likes to quote the dictum of Niels Bohr, the great Danish physicist, that, “An expert is a person who has found out by his own painful experience all the mistakes that one can make in a very narrow field.”

In October 1954 a newspaper in Richmond, Virginia printed an article about Harry M. Meacham who was a district manager for Dun & Bradstreet. He offered the following advice:8

“Success in management depends on building a strong staff. You do this by choosing people with the right attitude — the hardest part of the job — and giving them authority to act and room to make mistakes on which to grow. Someone defined an expert as one who made all the mistakes. . . .”

In 1962 by Edward Teller with Allen Brown wrote “The Legacy of Hiroshima” which contained the following passage:9

Back at Livermore, we started again. But our efforts this time were led by a group of real experts. An expert, according to a favorite definition of Niels Bohr, is a man who by his own painful experience has learned all the mistakes that can be committed within a narrow field. We at Livermore had made all the mistakes that seemed possible. We now were experts, and each year from 1955 to 1958 the laboratory brought in a rich harvest of unexpected and practical results.

In 1967 the “Los Angeles Times” of California printed the following remark from Dr. Eugene Kane of Reuss Davis Clinic:10

“And I’m supposed to be an expert,” he told a recent Parents Without Partners chapter meeting here. “An expert is one who has made all the mistakes. . .”

In 1972 The Wall Street Journal published the following thematic joke:11

Expert Tease
A consultant is a high-price expert who makes all the mistakes you would have made free of charge.
— Bill Copeland.

In 1977 “The Harvest of a Quiet Eye: A Selection of Scientific Quotations” compiled by Alan L. Mackay included the following entry with a different phrasing:12

Niels Henrik David Bohr 1885–1962
An expert is a man who has made all the mistakes, which can be made, in a very narrow field.
Edward Teller, 10 November 1972, US Embassy

In conclusion, this family of sayings began by 1904 when W. P. Northrup employed an instance in a medical journal. Werner Heisenberg used a different instance in a 1952 essay. Edward Teller credited Niels Bohr with another instance in 1954. The meanings of these three instances were distinct, but they form a natural group.

Image Note: Detail from the painting “Das Schulexamen” (“The School Exam”) by Swiss painter and illustrator Albrecht Anker circa 1862.

Acknowledgements: Great thanks to Edward Quine and Nigel Warburton whose twitter thread led QI to formulate this question and perform this exploration.

  1. 1954 September 6, LIFE, Dr. Edward Teller’s Magnificent Obsession by Robert Coughlan, Quote Page 61, Quote Page 62, Time Inc., Chicago, Illinois. (Google Books Full View) link ↩︎
  2. 1971 Copyright, Physics and Beyond: Encounters and Conversations by Werner Heisenberg, Translator: Arnold J. Pomerans, German Title: Der Teil und das Ganze, Chapter 17: Positivism, Metaphysics and Religion (1952), Quote Page 210, Harper & Row, New York. (Verified in hard copy) ↩︎
  3. 1904 November, The Chicago Medical Recorder, The Early Diagnosis and Treatment of Pneumonia in Infants by W. P. Northrup M.D. (Professor of Pediatrics in the New York University and Bellevue Hospital Medical College), Start Page 688, Quote Page 689, The Medical Recorder, Pub. Company, Chicago, Illinois. (Google Books Full View) link ↩︎
  4. 1913 March 22, Evening Kansan-Republican, Globe Sights of Atchison Globe, Quote Page 2, Column 4, Newton, Kansas. (Newspapers_com) ↩︎
  5. 1916 October 28, American Lumberman, Realm of the Retailer, Start Page 28, Quote Page 28, Chicago, Illinois. (Google Books Full View) link ↩︎
  6. 1938, Familiar Quotations by John Bartlett, Eleventh Edition, Edited by Christopher Morley and Louella D. Everett, Footnote, Quote Page 761, Little, Brown and Company, Boston, Massachusetts. (Verified with scans) ↩︎
  7. 1941 (1939 Copyright), The Boys’ Book of Photography by Edwin Way Teale, Chapter VII: Twelve Common Mistakes, Quote Page 88, Publication Note: First printing September 1939, E.P. Dutton & Company, New York. (Verified with scans) ↩︎
  8. 1954 October 11, The Richmond News Leader, Harry M. Meacham, Poet, Businessman by William Bien (News Leader Business Editor), Quote Page 24, Column 4, Richmond, Virginia. (Newspapers_com) ↩︎
  9. 1975 (Copyright 1962), The Legacy of Hiroshima by Edward Teller with Allen Brown, Part 1: The Work of Many People, Chapter 4: A Laboratory in the Cold War, Quote Page 66, Greenwood Press, Westport, Connecticut. (Verified with scans) ↩︎
  10. 1967 December 24, Los Angeles Times, Parents Urged by ‘Expert’ to Consider Hard Life of Children by Donna Sheibe (Times Staff Writer), Quote Page 2E, Column 4, Los Angeles, California. (Newspapers_com) ↩︎
  11. 1972 August 11, The Wall Street Journal, PEPPER….and Salt, Quote Page 4, Column 1, New York. (ProQuest) ↩︎
  12. 1977, The Harvest of a Quiet Eye: A Selection of Scientific Quotations, Selected by Alan L. Mackay, Section: Niels Henrik David Bohr 1885–1962, Quote Page 22, The Institute of Physics, Bristol and London. (Verified with scans) ↩︎