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.

The problem of having too many options available.

(object-oriented programming) The problematic situation where a base class contains methods which mutate an object in a manner which may invalidate a (stronger) invariant found in a derived class, violating the Liskov substitution principle. For example, if a circle is modelled as a subtype of an ellipse, and the ellipse has a method that stretches it on one axis, the circle must also implement that method despite it making no sense for a circle.

In decision theory, a kind of puzzle in which whenever an ideally rational epistemic agent is awoken from sleep, it has no memory of whether it has been awoken before. Upon being told that it has been woken once or twice according to the toss of a coin, once if heads and twice if tails, it is asked its degree of belief for the coin having come up heads.

A frustration or complaint only experienced by privileged individuals in wealthy countries. / {{quote-journal / For more quotations using this term, see Citations:first world problem.

Alternative form of measurement problem

(statistics) The bias to meta-analysis resulting from statistical studies with low statistical power tending to remain unpublished and inaccessible to the analyst.

The problem of finding a stable matching between two equal-sized sets of elements, given an ordering of preferences for each element.

(mathematics) A problem in combinatorics, in which 15 schoolgirls go walking three abreast for seven days in succession, and must be arranged so that no two walk abreast more than once.

(psychology) The phenomenon of autistic and nonautistic people mutually failing to understand each other due to cognitive differences in expressing and processing emotion.