Contested principles are pervasive in politics. In the most obvious cases, one side proposes a principle that the other side rejects. In this first case, both sides interpret the principle in the same way and anticipate similar applications of it. In this book we have focused on a second type of contested principle, principles that both sides accept in the abstract but that one side rejects because of the way others will interpret and apply it. Contested principles of this second type are found at all levels of political debate. In chapter 2 we examined simple assertions of moral right and wrong that are contested in this second sense. In chapter 3 we examined contested conceptions of the public good. In chapter 5 we examined the way persons who occupy legislative, executive, and judicial roles confront contested principles. In chapter 6 we looked at constitutional questions where the very rules that determine an agent's institutional role are themselves contested in this second sense.
Citizens, legislators, executive officials, and judges face a difficult moral choice when a situation such as this arises. They must decide whether, in the case at hand, toleration is the appropriate response. When these situations arise there is, by definition, some moral principle that the actor thinks valid or true. As a fact of human psychology, it is hard not to think one's own interpretation of the principle is the best one. After all, if you think someone else's interpretation superior, you should adopt it if you are acting in good faith. We thus face the classic paradox of toleration: If I believe a principle is right, why should I refrain from acting on the best interpretation of it? Part of the answer to this question, I have argued, rests on the fact that we have moral views on means as well as ends. The use of force and violence to achieve our goals and enforce our sense of right and wrong is suspect. That is not to say that it is always wrong, but it is to say that there is a presumption against it. To use force against another person is to make myself judge over that person and is in tension with respect for that other person as my moral equal. If a person is to legitimately use force or authorize its use against another, a simple appeal to one's own will or desire is not enough. Only appeal to a higher principle can satisfy the requirement that we show respect for the other person as morally equal.
I have argued that not all true moral principles automatically function as authorizations for force because they are not reasonable from a