Moral dilemmas do not tell us that moral principles/rules are useless. On the contrary, they give us the opportunity to clarify what the rule means. Rules or principles are also given content by the agents who apply them and the activities to which they are applied. The indeterminacy that remains once the rule has been made clear to us is a natural and inescapable component of all types of rule following and norm-based human action. Regardless of how rigid a rule is, following a rule according to the rule does not preclude judgment and decision. Hence, it always entails commitment and responsibility to the consequences of our action.

Thus, Sartre’s example of the student facing the dilemma of choosing between joining the French Forces or taking care of his ailing mother does not imply that rules and morality are non-existent or futile, e.g. the maxim of nationalism vs. the maxim of care or Christian doctrine and Kantian ethics. In this case whatever mode of action is permissible but those rules gave him a sense of what are at stake and the values we commit to by choosing one action and not the other. 

Thus the student says “In the end, it is feeling that counts; the direction in which it is really pushing me is the one I ought to choose. If I feel that I love my mother enough to sacrifice everything else for her – my will to be avenged, all my longings for action and adventure then I stay with her. If, on the contrary, I feel that my love for her is not enough, I go.”

While Sartre says that justification by means of a feeling is a form of vicious circle because the strength of a feeling is only defined with a corresponding action, the feeling itself is an aspect which cannot be separated from action which cannot be given by any rule. Yet it is a certainty that can be shared without requiring any justification. As Hume says, feelings are not always barriers to moral objectivity. In many cases, they are the very means through which we are able to define what counts as objective and what counts as the appropriate mode of action.