Palabras clave: Arendt; autonomia; Heidegger; Kant; Ortega y Gasset; responsabilidad.

Abstract: autonomy is a polysemous word, with at least four different meanings: 1) political, the classical one, as civil auto-government; 2) ontological, introduced by Kant as the very human condition, compared to the other nature beings; 3) legal, adopted by bioethics through the theory of informed consent; and 4) ethical, which links autonomy with responsibility. In an ethical sense autonomy has been a difficult, recent and minority achievement of human beings. Autonomous ethics arise in the modern age and only in the 20th century reach its maturity with the so-called ethics of responsibility, which requires that every autonomous decision and action is the result of an individual’s responsible judgement.