One thing we can say fairly conclusively is that, in a moral rule system that is articulated enough to cover much of the moral life, the rules must, as in the case of the norms discussed earlier, occasionally be in conflict with one another. For example, in one of the most contested remarks by any major moral theorist, Immanuel Kant holds that one is bound not to lie even when faced with an assassin who asks whether his intended victim is in one's apartment. Kant supposes that effectively turning over the intended victim to the assassin is a less grievous wrong than lying to the assassin. He writes that "although by a certain lie I in fact do no wrong to any person [such as the intending murderer], yet I infringe the principle of justice in regard to all indispensably necessary statements generally (I do wrong formally, though not materially); and this is much worse than to commit an injustice to any individual" (Kant 1909 , 365, final emphasis added; see further Hardin in press b, chapter 6). A rule to be trustworthy could run aground on Kant's account of his rule against lying. (Beware of such "moral" rules.)

XREF: Connects to Kant's absolute prohibition on lying and its tension with justice — relevant to work on deontological ethics and rule conflict. QUESTION: Worth interrogating how any articulated moral rule system could reconcile inherent rule conflicts; the assassin example provides a concrete test case.

Russell Hardin, Trust and Trustworthiness, loc. 220