The mathematical principle behind the “Smith Myth,” is now most commonly referred to as the Transposed Cards Principle. The foundation for this principle, which depends on the reversing of part or all of the deck, dates back to a card trick described in some of the earliest texts on conjuring secrets, such as “Trick for Guessing the Card from a Deck that Someone Else Has Thought of” from Pablo Minguet's classic, Engaños a ojos vistas, 1755 edition, p. 174 of the Pieper translation. This book was translated in Gibecière, Vol. 4 No. 2, Summer 2009, p. 61-225.
Professor Hoffmann, in Modern Magic, 1876, p. 52, provides two handlings of this trick in “To Allow a Person to Think of a Card, and To Make that Card Appear at Such Number in the Pack as Another Person Shall Name.” A bit more modern application was given by Walter Gibson with “The Transposed Cards” in Popular Card Tricks, 1928, p. 9.
Around 1955 (see The Magic Circular, Vol. 49 No. 546, Feb. 1955, p. 104), Sidney Lawrence published “Controlled Thoughts” in Ten Self Working Card Miracles (last page), an application of the principle that would become the basis for many to follow. One of those, and perhaps the the most influential of them in the twentieth century was Fred Smith's “Smith Myth” in Hen Fetsch's The Five-o-Fetsch, 1956, p. 7. It has been explored by Stewart James, , Nick Trost, Phil Goldstein and others. Another rudimentary form of the principle is active in a trick called “Mentalo” in Jean Hugard's Encyclopedia of Card Tricks 1936, p. 177.