Three Laws – more accurately, guidelines – for sf authors and other practitioners of Futures Studies or Prediction, stated by Arthur C Clarke in Profiles of the Future: An Inquiry into the Limits of the Possible (1962; rev 1973; rev 1984; rev 2000):
1. When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
3. Any sufficiently advanced technology is indistinguishable from magic.
#1 appeared as Clarke's Law in the original 1962 Profiles of the Future, with the cautious gloss that "elderly", in the disciplines of astronautics, Mathematics and Physics, means over 30. #2 can be found in the same chapter, though not designated as a law: it was termed Clarke's Second Law in the French translation, and a footnote in Clarke's 1973 revision of the text both acknowledges this and adds #3, which had first appeared in a published letter (19 January 1968 Science as "Clarke's Third Law on UFO's").
Writing on the popularity of Pseudoscience, Isaac Asimov proposed "Asimov's Corollary" (February 1977 F&SF) to #1:
"When, however, the lay public rallies round an idea that is denounced by distinguished but elderly scientists and supports that idea with great fervour and emotion – the distinguished but elderly scientists are then, after all, probably right."
The third of Clarke's Laws is the most quoted, and inspired another corollary by Barry Gehm: "Any technology distinguishable from magic is insufficiently advanced." (given as 1991 Analog but not traced). This is often wrongly ascribed to Gregory Benford, who quotes it in Foundation's Fear (1997). [DRL]
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