Meanings
- A puzzle of this kind: "You are given two indistinguishable envelopes, each containing money; one contains twice as much as the other. You may pick one envelope and keep the money it contains. Having chosen an envelope at will, but before inspecting it, you are given the chance to switch envelopes. Should you switch?" Because you stand to gain twice as much money if you switch while risking only a loss of half of what you currently have, it is possible to argue (fallaciously) that it is beneficial to switch.
Synonyms: exchange paradox, envelope paradox
Synonyms & antonyms
proper nounA puzzle of this kind: "You are given two indistinguishable envelopes, each containing money; one contains twice as much as the other. You may pick one envelope and keep the money it contains. Having chosen an envelope at will, but before inspecting it, you are given the chance to switch envelopes. Should you switch?" Because you stand to gain twice as much money if you switch while risking only a loss of half of what you currently have, it is possible to argue (fallaciously) that it is beneficial to switch.
Cite this entry
two envelopes problem. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/two%20envelopes%20problem
“two envelopes problem.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/two%20envelopes%20problem. Accessed November 4, 2026.
WatkinsX Dictionary, s.v. “two envelopes problem,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/two%20envelopes%20problem.
Source: two envelopes problem on Wiktionary, CC BY-SA 4.0.