Racionalitás

Racionalitás (rationality) is the quality of being reasonable and able to reason, form beliefs, and act in ways that are coherent with evidence, logic, and accepted norms. In philosophy and the social sciences, rationality is treated as a multi‑dimensional concept with normative and descriptive aspects. Normative rationality prescribes how agents should reason and decide, typically by maximizing expected utility under constraints or by maintaining coherent beliefs under probability theory. Instrumental or practical rationality concerns the selection of effective means to achieve goals given available resources. Epistemic or theoretical rationality concerns the adequacy of beliefs in light of evidence, logic, and scientific standards.

Historically, rationality has roots in ancient philosophy but was developed in modern times by figures such as Descartes, Kant, and later by Bayesian theorists and decision theorists. The Bayesian view treats rational belief as proportioned to evidence; decision theory links rationality to preferences and probabilities. Bounded rationality, proposed by Herbert Simon, recognizes cognitive and informational limits that constrain optimal reasoning.

In contemporary discourse, rationality is studied across disciplines: philosophy, cognitive science, economics, artificial intelligence, and political theory. It is subject to critique for being culturally contingent, for undervaluing non‑instrumental values, and for the role of emotions in decision making.