The envelope paradox dates back at least to 1943, when Belgian mathematician [[Maurice Kraitchik]] proposed a puzzle in his book ''Recreational Mathematics'' concerning two men who meet and compare their fine neckties.<ref name=brownkraitchik>{{Citecite journalbook |lastfirst=BrownMaurice |firstlast=Aaron C.Kraitchik |yearauthorlink=1995Maurice Kraitchik |title=Neckties,"Mathematical Wallets, and Money for NothingRecreations" |journalpublisher=[[JournalGeorge ofAllen Recreational& Mathematics]]Unwin |volume___location=27London |issueyear=2 1943|pagesurl=116–122 https://archive.org/details/mathematicalrecr0000maur}}</ref><ref name=kraitchikbrown>{{citeCite bookjournal |firstlast=MauriceBrown |lastfirst=KraitchikAaron C. |authorlinkyear=Maurice Kraitchik1995 |title="MathematicalNeckties, Recreations"Wallets, and Money for Nothing |publisherjournal=George[[Journal Allenof &Recreational UnwinMathematics]] |___locationvolume=London27 |yearissue=19432 |urlpages=https://archive.org/details/mathematicalrecr0000maur116–122 }}</ref> Each of them knows what his own necktie is worth and agrees for the winner to give his necktie to the loser as consolation. Kraitchik also discusses a variant in which the two men compare the contents of their purses. He assumes that each purse is equally likely to contain 1 up to some large number ''x'' of pennies, the total number of pennies minted to date.<ref name=kraitchik/>
The puzzle is also mentioned in a 1953 book on elementary mathematics and mathematical puzzles by the mathematician [[John Edensor Littlewood]], who credited it to the physicist [[Erwin Schrödinger]], where it concerns a pack of cards, each card has two numbers written on it, the player gets to see a random side of a random card, and the question is whether one should turn over the card. Littlewood's pack of cards is infinitely large and his paradox is a paradox of improper prior distributions.
