Explaining Ethics Part 6 Kant illustrates the logic of his formulation of the categorical imperative with the example of promise keeping. Suppose I cannot get a loan without promising to repay it, but I know that I will never be able to do so. If I promise to repay and I take the loan, then could I reasonably determine a categorical imperative from my action? It would have to be, 'make promises to secure your wishes even if you cannot keep them'. Such an imperative would be self-defeating: promise-keeping would fall into disrepute and nobody would ever trust another's word. It would be contrary to what is meant by a promise.

This sounds all well and good. But the question I have about the categorical imperative is this: Which features of your action should be put into the general rule? It's possible that, in the example given above, "make promises to secure your wishes even if you cannot keep them" would be the general rule. But why not "make promises to banks to secure your wishes even if you cannot keep them"? What about "make promises on Fridays to secure your wishes even if you cannot keep them"? What about "make promises only if you cannot keep them"? If you're only working from one data point, there are an infinite number of universal rules you could claim to be adhering to, some of such specificity that they would hardly create the social problems foreshadowed by making all promises meaningless. The categorical imperative becomes simply an injunction against hypocrisy -- that is, judge others' actions the same as your own unless there is a significant difference between them. That's not exactly a profound insight.