Morality

[L:77] Kant holds that moral truths, like "philosophical truths of reason", cannot merely be believed, "but must be known". He writes, "as concerns particularly the objects of reason's practical cognition in morality--rights and duties--there can be in respect of these just as little a mere believing. One must be completely certain whether something is right or wrong, according to or contrary to duty, licit or illicit. In things moral nothing can be ventured on an uncertainty, nothing at the risk of an offense against the law".

See Situation ethics