Karl R. Popper’s philosophy is principally oriented in two principal lines of study: epistemology and political philosophy. Popperian reflection in political philosophy reveals an unequivocal and explicit ethical commitment. Our article seeks to examine this commitment, showing that it is also present in Popper’s general epistemological perspective, and especially in his demarcation criterion. Furthermore, always from the optic of this Austrian-Britisch philosopher, we highlight the constructive role that the emergence of failure has in knowledge development.La filosofía de Karl R. Popper se orienta, principalmente, según dos grandes líneas: la epistemología y la filosofía política. En lo que respecta a esta segunda vertiente, la reflexión ...