or worthlessness, off an action, so that the same act may deserve condemnation or praise according to the intention which determined it. Hence it is that, whenever men discuss a proceeding to which some moral importance is attached, the intention is always investigated, and by this standard alone the matter is judged; as, likewise, it is in the intention alone that every one seeks justification, if he see his conduct misinterpreted or excuse, if its consequence be mischievous.

On p. 14 (R., p. 20) we at last reach the definition of Duty, which is the fundamental conception of Kant's entire ethical system. It is: “The necessity of an action out of respect for the law.” But what is necessary takes place with absolute certainty while conduct based on pure duty generally does not come off at all.