contigency

Contingency refers to the dependence of events on chance, or to events that may happen but are not guaranteed. The term derives from Latin contingere, "to happen, befall." In philosophy and modal logic, a proposition or fact is called contingent if it could be true or false in different possible worlds, in contrast with necessary truths that could not be false. Contingency thus contrasts with necessity and with impossibility, and it underpins discussions of freedom, determinism, and chance.

In probability and statistics, a contingent event is one whose occurrence is not certain; its probability is between 0 and 1. Contingency tables (cross-tabulations) examine the relationship between two categorical variables and are analyzed with tests such as chi-squared to assess independence.

In practical contexts, contingency often refers to planning for unforeseen events. Contingency planning develops backup options to maintain operations during disruptions, such as supply chain delays, natural disasters, or financial shocks. Organizations may establish contingency funds, or reserves, and disaster recovery or business continuity plans to mitigate risks.

Contingency is also used in everyday language to describe dependability on external factors, or to acknowledge that outcomes are not predetermined. The common misspelling contigency is widespread; the standard spelling is contingency.