quality:corruption
Universalizability

Kant believed that morality is the objective law of reason: just as objective physical laws necessitate physical actions (e.g., apples fall down because of gravity), objective rational laws necessitate rational actions. He thus believed that a perfectly rational being must also be perfectly moral, because a perfectly rational being subjectively finds it necessary to do what is rationally necessary. Because humans are not perfectly rational (they partly act by instinct), Kant believed that humans must conform their subjective will with objective rational laws, which he called conformity obligation. Kant argued that the objective law of reason is a priori, existing externally from rational being. Just as physical laws exist prior to physical beings, rational laws (morality) exist prior to rational beings. Therefore, according to Kant, rational morality is universal and cannot change depending on circumstance.