Rationality and Ethics

The word logos was used in Greek philosophy to refer to rationality. Logos was adopted by the Romans as ratio, which became rationality in English. Rationality, like ethics, is considered a uniquely human characteristic, a characteristic that distinguishes humans from other life-forms. Aristotle used logos to describe humans as rational animals, animals that are capable of knowing in the cognitive and moral sense. This Aristotelean notion of the interdependency between rationality and ethics is a characteristic broadly accepted in classical Greek philosophy.

In Roman and medieval times, rationality was associated with religious thought and belief. This association was severed during the Renaissance and the Enlightenment, when the relationship between ethics and religion was questioned. As a consequence, rationality became the characteristic of autonomous persons who possessed the capacity to develop their own morality because of their capacity to be rational and were in no need of external authority or imposed values.

In addition to the focus on the individual during the Enlightenment, rationality became associated with scientific method and gave birth to the rationalist school of thought. This school of thought claims that knowledge and truth are based on reason, not on external sources or value judgments. Rationality then became associated with utility in value-free science. This development led to scientific rationality, which is based on positivism, the perspective that perceives value judgments as incapable of being rational, and rational judgments as those that relate to utility.

Rationality underwent radical transformations in its journey through history. From the coexistence of rationality and ethics during the classical Greek period, rationality became the source of morality during the Enlightenment. More recently, rationality is generally associated with utility and efficiency rather than ethics.