Irrasjonelle

Irrasjonelle is a Norwegian adjective meaning irrational. It describes ideas, actions, or beliefs that lack rational justification or logical coherence. The form irrasjonelle is used when describing plural nouns (for example, irrasjonelle handlinger), while irrasjonell is used with singular nouns. The term derives from Latin irrationalis, passing through medieval and modern European languages and entering Norwegian as part of the broader adoption of scientific and philosophical vocabulary.

In mathematics, the cognate concept is the property of numbers that cannot be expressed as a ratio of two integers. In Norwegian-language texts, this mathematical idea is usually described with terms that translate to irrational numbers (often discussed as irrationelle tall or irrationelle tallsett in various sources). Examples commonly cited are the square root of 2 and pi, which have non-terminating and non-repeating decimal representations.

In philosophy and cognitive science, irrasjonelle describes beliefs, judgments, or decisions that do not follow evidence or logical reasoning. Discussions of rationality, decision-making, and cognitive biases frequently address irrasjonelle elements, noting that emotions, heuristics, social factors, and incomplete information can influence judgment in ways that appear irrational.

See also rationality, rational, irrational.