Sturgeon's law (or Sturgeon's revelation) is an adage stating "ninety percent of everything is crap". It was coined by Theodore Sturgeon, an American science fiction author and critic, and was inspired by his observation that, while science fiction was often derided for its low quality by critics, most work in other fields was low-quality too, and so science fiction was no different.[1]

The cover of the September 1957 issue of Venture Science Fiction, in which Sturgeon first published "90% of everything is crud."

The original Sturgeon's law


Sturgeon deemed Sturgeon's law to mean "nothing is always absolutely so".[2] This adage previously appeared in his story "The Claustrophile" in a 1956 issue of Galaxy.[3]

The second adage, variously rendered as "ninety percent of everything is crud" or "ninety percent of everything is crap", was known as "Sturgeon's Revelation", formulated as such in his book review column for Venture[4] in 1957. However, almost all modern uses of the term Sturgeon's law refer to the second,[citation needed] including the definition listed in the Oxford English Dictionary.[5]



A similar adage appears in Rudyard Kipling's The Light That Failed, published in 1890.

Four-fifths of everybody's work must be bad. But the remnant is worth the trouble for its own sake.[6]

A 1946 essay Confessions of a Book Reviewer by George Orwell asserts about books:

In much more than nine cases out of ten the only objectively truthful criticism would be "This book is worthless ..."[7]

According to science fiction author William Tenn, Sturgeon first expressed his law circa 1951, at a talk at New York University attended by Tenn.[8] The statement was subsequently included in a talk Sturgeon gave at a 1953 Labor Day weekend session of the World Science Fiction Convention in Philadelphia.[9]

The first written reference to the adage is in the September 1957 issue of Venture:

And on that hangs Sturgeon’s revelation. It came to him that [science fiction] is indeed ninety-percent crud, but that also – Eureka! – ninety-percent of everything is crud. All things – cars, books, cheeses, hairstyles, people, and pins are, to the expert and discerning eye, crud, except for the acceptable tithe which we each happen to like.[4]

The adage appears again in the March 1958 issue of Venture, where Sturgeon wrote:

It is in this vein that I repeat Sturgeon's Revelation, which was wrung out of me after twenty years of wearying defense of science fiction against attacks of people who used the worst examples of the field for ammunition, and whose conclusion was that ninety percent of S.F. is crud.

The Revelation
Ninety percent of everything is crud.
Corollary 1
The existence of immense quantities of trash in science fiction is admitted and it is regrettable; but it is no more unnatural than the existence of trash anywhere.
Corollary 2
The best science fiction is as good as the best fiction in any field.[10]

In 2013, philosopher Daniel Dennett championed Sturgeon's law as one of his seven tools for critical thinking.[11]

90% of everything is crap. That is true, whether you are talking about physics, chemistry, evolutionary psychology, sociology, medicine – you name it – rock music, country western. 90% of everything is crap.[12]

Its re-introduction to a modern audience received a positive reception, according to Dennett.[13]

See also



  1. ^ Charles Clay Doyle; Fred R. Shapiro; Wolfgang Mieder, eds. (2012), The Dictionary of Modern Proverbs, Yale University Press, pp. 76–77, ISBN 9780300183351
  2. ^ Sturgeon, Theodore (July 1957). Mills, Robert P. (ed.). "ON HAND: A Book". Venture Science Fiction. Vol. 1, no. 4. Fantasy House, Inc. p. 78.
  3. ^ "The Claustrophile", Galaxy August 1956
  4. ^ a b Sturgeon, Theodore (September 1957). Mills, Robert P. (ed.). "ON HAND . . . Offhand: Books". Venture Science Fiction. Vol. 1, no. 5. Fantasy House, Inc. p. 49. Retrieved 14 July 2023.
  5. ^ "Sturgeon's Law". Oxford English Dictionary. Retrieved 6 January 2019.
  6. ^ Kipling, Rudyard (1897). The Writings in Prose and Verse of Rudyard Kipling. ISBN 9785874724696.
  7. ^ Orwell, G. (1946). Confessions of a Book Reviewer.
  8. ^ "Historical Dictionary of Science Fiction: Sturgeon's Law". Retrieved 15 November 2022.
  9. ^ "Sturgeon's Law". Retrieved 15 January 2023.
  10. ^ Sturgeon, Theodore (1958). "Books: On Hand". Venture Science Fiction. Vol. 2, no. 2. p. 66.
  11. ^ Dennett, D. (21 May 2013). "Daniel Dennett presents Seven Tools for Critical Thinking".
  12. ^ Dennett, D. (2013). Seven Tools for Critical Thinking.
  13. ^ Dennett, D. (10 June 2013). Daniel Dennett tools for thinking. Point of Inquiry (Audio recording). Event occurs at 39ᵐ.