Clarke's first law was proposed in the 1962 edition of the essay, as "Clarke's Law" in Profiles of the Future. The second law is offered as a simple observation in the same essay but its status as Clarke's second law was conferred by others. The author proposed the third law in the 1973 revision of Profiles of the Future.
The third law, despite being latest stated by a decade, is the best known and most widely cited. It echoes a statement in a 1942 story by Leigh Brackett: "Witchcraft to the ignorant, … simple science to the learned". Earlier examples of this sentiment may be found in Wild Talents (1932) by Charles Fort: "…a performance that may some day be considered understandable, but that, in these primitive times, so transcends what is said to be the known that it is what I mean by magic," and in the short story The Hound of Death (1933) by Agatha Christie: "The supernatural is only the natural of which the laws are not yet understood."
Clarke gave an example of the third law when he said that while he "would have believed anyone who told him back in 1962 that there would one day exist a book-sized object capable of holding the content of an entire library, he would never have accepted that the same device could find a page or word in a second and then convert it into any typeface and size from Albertus Extra Bold to Zurich Calligraphic", referring to his memory of "seeing and hearing Linotype machines which slowly converted ‘molten lead into front pages that required two men to lift them’".