Sturgeon's Law

Sturgeon's revelation, commonly referred to as Sturgeon's law, is an adage commonly cited as "ninety percent of everything is crap". It is derived from quotations by Theodore Sturgeon, an American science fiction author and critic; while Sturgeon coined another adage that he termed "Sturgeon's law", it is the "ninety percent crap" remark that is usually referred to by that term.

The phrase was derived from Sturgeon's observation that while science fiction was often derided for its low quality by critics, it could be noted that the majority of examples of works in other fields could equally be seen to be of low quality and that science fiction was thus no different in that regard from other art forms.

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."

The first written reference to the adage appears in the March 1958 issue of Venture, where Sturgeon wrote:

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 SF is crud. Using the same standards that categorize 90% of science fiction as trash, crud, or crap, it can be argued that 90% of film, literature, consumer goods, etc. is crap. In other words, the claim (or fact) that 90% of science fiction is crap is ultimately uninformative, because science fiction conforms to the same trends of quality as all other artforms.

According to Philip Klass (William Tenn), Sturgeon made this remark circa 1951, at a talk at New York University attended by Tenn. 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.

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